Marcos Maniacs

I'm a newbie to this group and to Marcos' in general.  So, if this 
info is elswhere, please forgive my ignorance.

Anyway, I've just started digging into this '69 wood-chassis 3000 
project, and inventorying necessary items.  My question is that for 
those of us in the U.S., where do you find parts for cars that were 
never imported - like the ones shown in the parts list I found here -
 for the Cortina, Zodiac and Vitesse?  I know many of the usual 
sources for the more common U.S. spec cars - even for my TVRs, but 
if any of you could get me started in the right direction, I'm sure 
it'll save me a lot of time and aggravation...and get another Marcos 
back on the road that much faster.

Thanks in advance,
-Bob