stage3_rx7

i have a '90 GTUs with a high bridge,holley 600cc double pumper,act bronze clutch w/o springs,heavy duty press. plate,r.b headers,custom 2.5" exhaust,And some other things.Its my 6mpg daily driver . I think I need a new rear end and transmission. I have done some damage to them. i grind into 2nd and 3rd. and it chatters when i launch. Where could i get a "race ready" transmission,drive shaft,and rear end?

stage3_rx7

Would you think that mazsport would have it?