+1 for Dawson and Brazos. I've purchased STIs from both and was very pleased. They both really know STI guns and were easy to work with. In the current environment they are also probably your best bet for finding what you want as they carry a larger inventory than almost anyone else. My local range owner is a big STI fan and usually has a good selection, but he's almost cleaned out.
STI-Eagle(2)/Trojan(2)/Edge/Guardian/VIP/Rogue/Ranger III/Sentinel/Tactical 4.0/Escort; Remington Rand-1911A1; Ruger Redhawk/Blackhawk; Sig P238