John,
Obviously you've been looking at the wrong Cobras. Theres only two types that have the 4 cylinder engine, even then many people then swap it for a V8, and theres probably a good five or six other makes that are made specifically for V8s from Rover 3.5 litre even up to Big Blocks.
Lots of guys in Holland buy UK sourced kits ( made for lhd )or even completely finished Cobras, one of our members builds beautiful examples as his business, and the UK Cobra Replica club
www.cobraclub.com has members all over Europe.
Drop by the website and ask a few questions of us Brits we'll be more than happy to help.
Cheers,
Tony