A 60mm TB from a 7m series will bolt up to the upper plentum of a 22RE.
The plentum (upper) will have to be ported somewhat, perhaps 5mm.
For reference the stock TB is 55mm
LC will provide a 58mm TB for around $290.
I don't have a write up on this, the TB itself will bolt up - all the same hose functions are there, but will have to be re-routed.
The throttle cable can be made to work with minor adaptation from the stock 55mm TB. I had to weld a tab for the "close" set screw. I haven't setup the WOT stop yet.
These are very available and cheap. The TPS is the same on my 88, but it looks like a bolt-in-place deal even the TPS had to be replaced.
This is how it started life:
Now adatped to a late model 22RE upper manifold.
Photos - I had it powdercoated black, so the contrast isn't excellent:
Mock up of intake on this motor:
