Unless things have changed, both RSM and Brodak sell Thunderbird kits and will sell plans, wing ribs or other parts for anything they kit. I'm not really very "up" on what Brodak kits, but know that RSM kits the '59 T-Bird and Brodak kits the earlier T-Bird.
I don't see any reason to buy a "short kit" from UK and pay the shipping plus wait for the customs folks to inspect and possibly break what you bought. Both RSM and Brodak kits are laser cut, anyway.

Steve