Your most economical choices are going to be a T-5 or a TKO - both five speed manuals. A T-56, a six speed, is an option but requires a lot of rework. the T-5 will handle a maximum of 300 lb-ft of torque while the TKO will handle 500 - 600 lb-ft. The T-56 will handle up to 450 lb-ft. Running sticky tires will put much more strain on the tranny than if you run a set of hi-po radials. The radials will break free and spin well before the max torque of the transmission.
The SN95 bodies require special T-5's with a longer tail stock to use the stock drive shaft. The TKO or T-56 will require a custom drive shaft. The T-56 will also require a special (read "expensive") bell housing. The T-5 and TKO can use a bone yard piece.