If you take a look at the Jerry Campbell collection that is for sale here on the forum you will see what a contemporary of Bryce,at OKCity PD, carried his Third model HE .44 Spl. in, a Threepersons style holster made by A. W. Brill of Austin Texas with accompanying cartridge belt slide.

Both of these items speak to the gun knowledge these men possessed in an era that saw the majority of Officers carrying a .38 Special loaded with 6 rounds and no spare ammo.

Most every town in America had at least one leather shop, and while in the early part of the 20th century their stock in trade was saddle/harness gear, and footwear, many of them also made holsters and other items. Unless they marked their work their names are lost to history.

The only holster maker in OK City during that period I can think of was Andy Card. I am sure there were others.

Maybe someday more info will surface beyond Ron Owens's outstanding book on D. A. "Jelly" Bryce.