85 Celica GTS Side Marker

[tsswclb]

I have a 1985 Cellica GTS whose front side marker's are crumbling due to age. I have found replacement parts via the net labeled "Side Marker Assembly" (e.g. sku 18-1153-50). Online chats with several of the vendors (who all seem to share the same catalog information) indicate the "assembly" only includes the lens (not much of an assembly). I also need the backing plate (or whatever it is called). Does anyone have experiences with these OEM side marker assemblies? Any other advise on finding replacement parts would also be welcome as I love the car and want to fix it right.

Thanks In Advance
Curt