I have been pondering a Cobra build for so may years many of the jerks in the business went out of business due in a large part to Cobra Country. First visit Cobra country get the "Cobra Manual". This will give you some excellent advice in what to look for, what to expect and what to watch out for; next find a local club and talk to the various owners with different makes, great info available here. Remember most owners love their cars to death and each one is going to protect their "builder" as evidenced by this site.
Buy what you can afford and build the car for you. It will be yours, you may not want a perfect "replica" or you might want to; you may not want a 4 spd, Ford or God forbid want an automatic
Build it for you and no one else.
This site combined with Cobra Country will give you a wealth of information. As you can see from my title page I have selected an ERA. This is not to say the others are not good or bad. My reserach, desires, my capability in affording and or building was all in consideration.
Most of all have fun and enjoy the choices you have to make, because once you've made the choice the other choices become fun, hard, always changing
and will be happening until it becomes part of the Cobra.
Dennis