Reinstalling factory louvers

We have a 1978 280Z Black Pearl and while doing some restoration we removed the rear hatch louvers. Well, as you can imagine, after 32 years the fasteners holding the hinges and latches to the body were pretty much fused together and instead of unscrewing they came out in one piece. These look like some sort of expansion type arrangement but were so rusted it's hard to tell. Does anyone have an idea of where we might acquire replacements?