Re-trim the original seats in these:
http://coffeebeanbags.com/default.asp
Seriously, I think it'll match the 'theme' really well and IMO is pretty cool. Saw on old Type 2 done this way at VolksWorld this year and it got loads of attention.
The missing arch trim, on the vandalised wing is bothering me.
Basically, I don't take my car seriously!