Hi Dan!
Take a look at Olthoff (
www.olthoffracing.com)- and give Dennis Olthoff a call. (he does not like mails and the website is not actual)
Dennis and his crew is in North Carolina - he is a straight shooter and have lots of experience in Superformance. He is a great person to deal with and when you need parts or advices he will help you a lot.
And the important thing: when he told you a car is good then it is really good and you waist no time and travelling costs. Nothing worse as a flight to the states for a crappy car!
To raise your budget to 50.000 or 55.000 will help - try to get a perfect car - it will be cheaper at the end (shipping parts and taxes to Europe makes no fun) - and with import the car to Roterdam you will save some of the additional costs.
One other point...your car should have a 1965 or 1966 title!!!! 15" wheels are ok but the only good tire is the Avon and they are expensive - so 17" wheels will not be correct but will safe money and give you a plus in safety.
Greetings from icecold Austria
Peter