I'd have to agree the likelihood of seeing a repro of those fields is pretty damn low. Same with the plastics...and the two big ones are often broken, the ones that serve as aprons, where that long skinny piece goes up the side of the playfield.
I've owned 2 Jousts but way back in the day before the prices went completely insane. Shipped my nice one to Darin from Phoenixarcade and the shipper managed to tip it off the end of the liftgate at the destination, broke the legs, smashed the glass, and busted up one of the lockdown bars. :/
Wouldn't mind owning another but it's not worth the price to me, these days.
Richard