The British-English phrase we’ve got a right one here, and variants, are used of an odd person or of an idiot.

Typically, the speaker uses this phrase when talking to someone about a third party.

These are, in chronological order, the earliest occurrences of the phrase we’ve got a right one here, and variants, that I have found:

1-: From the caption to the following cartoon, published in the Daily Mirror (London, England) of Friday 7^th February 1958:

“I’ve got a right one ’ere!”

2-: From the caption to the following cartoon, published in the Evening Standard (London, England) of Thursday 28^th August 1958:

“Head office? We’ve got a right one here, wants to borrow £500 to invest in a hire-purchase trust company.”

3-: From an advertisement for Fibreglass, Limited, St. Helens, Lancashire, published in The Guardian (Manchester, Lancashire, England) of Tuesday 25^th October 1960:

“A comforting thought, is it not?”
murmured the Turncock, “that the water pipes which, indirectly, I am controlling, are wrapped in Fibreglass Reinforced Tissue. The amazing strength of this tissue, its low cost and indefinite life, are a byword among pipemen. Moreover, it affords immediate bleed-through of asphaltic or coal tar enamels, and provides all the protection against corrosion and soil stress that any underground pipe could wish for.”
We’ve got a right one here, thought the foreman. But there’s no denying the truth of what he says.

4 & 5-: From the captions to the following Useless Eustace cartoons, by Jack Greenall (1905-1983), published in the Daily Mirror (London, England):

4-: Of Thursday 31^st August 1961:

“I’ve got a right one ’ere, Sarge!—Says ’e got lit up so ’e could see ’is way ’ome in the dark!”

5-: Of Friday 15^th February 1963:

“Got a right one ’ere! Name of applicant . . . EUSTACE. . . . Name of Wife . . . WINNIE. . . . Names of Parents . . . MUMMY AND DADDY!”

6-: From About motoring: Encounter with a bollard, by P. W. J. Riley, published in The Guardian (Manchester, Lancashire, England) of Monday 23^rd December 1963—the author tells what happened after his car hit a bollard:

I got in touch with my insurance company. They sent me a claim form. It was then that I realised the true enormity of what I had done.
“State what weather conditions existed at the time of the accident.” All I could say was that it was dry, fine, and sunny.
“State what other vehicles were involved.” None.
“State what exactly happened, to the best of your knowledge, drawing a diagram if possible. The diagram should show the position of your own and other vehicles, together with the direction in which they were travelling.” I drew a diagram showing my vehicle, the refuge with bollard, and, by dotted lines, my solitary course across the road and over the bollard. I posted the claim and had a vision of some official of the company showing it round the office saying, “We’ve got a right one here.”

7-: From the caption to the following cartoon, published in the Daily Mirror (London, England) of Tuesday 3^rd November 1964:

“I’ve got a right one here—he’s invented colour radio!”

8-: From Small ‘boy’ was driving a car . . ., published in the Liverpool Echo and Evening Express (Liverpool, Lancashire, England) of Tuesday 29^th November 1966:

A motor police patrol on duty in Lancashire spotted what they thought was a small boy driving a car, and went after him in a chase which ended when he was overtaken and stopped.
One of the policemen walked grimly back to the car, getting his notebook ready. The “boy” in the car grinned.
“Hullo, officer,” he said, “I’m Jimmy Clitheroe *.”
This kind of thing is always happening to this 4ft. 3in. tall, ageless schoolboy, who is to star in “Tom Thumb,” the pantomime at the Royal Court Theatre, Liverpool, this Christmas season.
“I’ve had ’em chasing after me on bicycles, probably thinking they’ve got a right one here,” said Jimmy.

* James Robertson ‘Jimmy’ Clitheroe (1921-1973) was a comic entertainer born and bred in Lancashire.

9-: From the following letter, published in the Daily Mirror (London, England) of Thursday 11^th May 1967:

Cockeyed and cackhanded!
Mrs. HEATHER ARBEITER, of Woodston, Peterborough, Northants, writes:
I can’t help wondering whether Mrs. Freeman, who reads your letters from right to left, is left-handed. Being left-handed myself, I find I always read papers and magazines from the last page through to the first. I usually begin books from the middle, reading to the front, and then the remainder from the back!
It’s easier for me to turn the pages from right to left than from left to right.
I can hear you thinking: “We’ve got a right one here!”
► A right one? Reckon you’re a bookworm with a left-hand thread!