Afraid I can't help with 3D files but couldn't help but comment on your user name. While I now reside in the SF Bay Area, I was born in England, and the Sinclair ZX81 was my first computer. Wow, I haven't heard that name in years!! Good luck with your quest.
My "rejuvenation" blog: http://65tomfoolery.wordpress.com
'65 Alfa Giulia Sprint GT, a long way to go stillÖ.