I sold my '75 Baja to someone on the list that had as much original paperwork as anything I've ever seen period, plus original keys AND Stroppe key ring. Show me an original key ring and I'll be impressed. Documents included Stroppe invoices, window sticker, dealer card, Cali Blue plates and dealer plate frame, original spare tire cover, and a ton of other stuff. I know what I sold mine for.
Anyway, it's only worth what someone will pay for it...which is probably low 20's in my opinion.