Don't have a TRD unit (Mine is more of a "Supra/Cressida Hybrid") but have priced the TRD units for the MX83. (Sit down though, 'cos they ain't cheap!) You can get them through TRD NZ (whose web-site escapes me ) Trust me, I've been to the TRD Japan web-site (English version) got the part numbers of stuff (in my case I was looking at 4-way adjustable TRD shocks and struts for the '83) and then I actually phoned the NZ guys, quoted the part number, and they quoted on it...
As for the diff, prepare to pay around $2000 for it.