Yes that looks like the factory style frame mounted hitch. You'll need the ball mount/ draw bar and a pin to hold the bar in; I prefer a locking version because it makes it more difficult for someone to steal your trailer by removing the pin and pulling the draw bar out. These are pretty much a standard size. I believe the pin hole is 5/8" or 3/4 " .
If I could get out and about - I'd know by now if they are common in the UK. What traffic there is passing the house is too fast for me to check their hitches! Definitely what is there is factory GM.
The original owner may not have ever had a draw bar if they didn't need to tow a trailer. Probably just needed a Burb to move dignitaries around comfortably LOL
I suspect you are spot on there. Then subsequent owner used the roof rack - and judging by the wear pattern on the paint, my guess is canoes.
Before any of you start wondering if I am 20 feet tall.... Nope, I have upstairs windows in the house.
And, seeing as this thread has kinda turned into a blogpost (and without hyjacking someone else's thread for a change) more news on my Burb, particularly its crooked steering wheel. Had a go at repositioning the Pitman arm after wondering if I'd be able to remove the retaining nut. Worried needlessly about that. I reckon the garage that fitted it misread 184lb.ft as 18.4lb.ft. Seriously!
The arm wasn't keen to budge so before I fell out on it I had a look at the splines and mine has a master spline so no point in going any further than thumping the nut back on and heading back indoors as the rain began. Next is attempt the adjustment at the gearbox input shaft - once I figure how to shift the plastic shroud it's hiding behind. Any and all suggestions welcomed!.....