[65 CobraCharlie]

Hi everyone, another newbie here. I'm really enjoying this forum and have already learned a lot in my first day. My name is Charlie and I live near Asheville, NC. My wife and I dream of owning a completed Cobra kit
I have a question that I have not seen addressed here (sorry if I just missed it).
After searching this site and EBay, I notice that many engines and transmissions have been modified. Are there any known sellers that use stock Ford engines and transmissions? Since I live in a somewhat remote area, I would like to have a car that a general Ford mechanic could work on (if the work is too much for me). I just get a little nervous when I see the comments about bored engines, aftermarket electronics, etc. A stock 4.6 or 5.0 type Ford engine, with matching 5 speed would be acceptable. My budget is $30-40k.
Any input would be greatly appreciated.