Mine is a 2nd Gen not 1st so maybe there aren't any 'used' options but I found a donor vehicle and swapped interior upholstery & trim pieces. I bought the donor for $500 and have swapped a bunch of parts; I believe I can still get $500 for it once I'm finished swapping parts.
Used 2nd gens (especially 2WD) and plentiful and cheap in my area
Here are a few before/after photos I posted in my 'New Member' thread. I need to move this over and start a build thread.
First 4Runner
Anyways, good luck with the project!!