Please feel free to check out some of the links below.
These are some of the sellers and manufactures that I support.
Many of them
Del Quadro Custom Trumpets - Mike is the maker of my trumpet, the Del Quadro Grizzly. My horn has been customized with a reversed sleeved lead pipe. It's the best horn that I've played and I love it. He also does great repair work and at a very reasonable price.
Austin Custom Brass - Store owned by Trent Austin, a fine musician and a seller of fine brass instruments.
Torpedo Bags - Makers of some of the finest cases. Made in the USA. I use their Coyote Case with the "Snarl" lid.
Kanstul Instruments - Based out of Anaheim, CA. They make quality brass instruments. I use their 1525 flugelhorn.
James R. New Mouthpieces - James R. New is a master at mouthpiece making. He has recently gone into business for himself after working for decades at Kanstul. I currently play his S5 series for both trumpet and flugel.