Well, the carby is really the 'Achilles' Heel' of Tecumseh engines. And OEM parts are very thin on the ground now.
If you read a few of the threads in this section of the forum, the prevailing ODK attitude is to just replace the entire carby. Just watch the fuel inlet elbow material on the aftermarket carbies - I'd avoid the plastic ones.
That kit doesn't look like the right one for a TVS90 engine. This webpage has useful info on OEM/aftermarket part numbers for these kits:
http://www.psep.biz/store/tecumseh_carburetor_kits.htm