MR2, Acura Integra, CRX, Miata, etc. Look for ones that fit you, are well bolstered, and go from there. Brackets are relatively easy to fabricate and require little welding if any.
BTW, some Plymouth Lasers and Dodge Challengers had some cool Mark Cross leather seats that are the bomb. Most are electric and have lumbar adjustments too. Not as simple as the cars above, but for $5 a seat, what do you care?
Just some thoughts.
Davy