You could try Toyota and see if they still sell them:
http://www.toyodiy.com/parts/p_G_1984_TOYOTA_COROLLA_AE71RG-EYKRCQ_3101.html
Otherwise, C52 (in some FWD Corollas) clutch fork and throwout bearing will work in a T50, I've tried it and it seemed fine. Trev on here said he has done it too.