I reckon a 1275 can be made to spin on a 22G68, they were used on 997 and 998 Coopers. You would need to do a bit of fettling of the front edge and the centre web (usually) with a die grinder.
The example I gave above that needed hacking was an early 850 box.. it was all I had back then.
I have a Morris 1100S box here I'll never use, if it helps you...
1st gear in it is stripped, but the rest seems fine. Going real cheap (beer money).
Not sure of the gearbox number, can check tomorrow. I bought it just for the 1100S donk on top.
_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.
