Much of the leather was actually 'real', period gear - purchased by prop men everywhere.
You'll see a lot more of it being worn by the background actors - along with original saddles and clothing - especially if the film's been colorized.
The 'hero' was the guy who got the 'Fast Draw' rig and the better-fitted clothing - everyone else got what might fit.
By the '40's, Buscadero rigs were widely seen being worn by the principals who might actually have to pull the piece - the original, period rigs - worn high, with deep hulls - were somewhat difficult to draw from as quickly as the film demanded.
Scouts Out!