Or a much simple pants alteration:
Sew fuzzy velcro inside the cargo pocket against your leg, and sew/glue/attach opposing velcro to the holster and velcro the holster in place inside the pocket.
Hell, 5-11 Tactical makes their Class B uniform pants this way already, (with the fuzzy velcro in the pocket) and sells the nylon holsters with velcro on the outside as accessories for $19.99 each. You could just buy a velcro 5-11 holster and sew velcro into your existing pants pockets. I bet it would be much more comfortable too.
Go to
www.511tactical.com and click on the "Back-up Belt System" link on the left column for the holster.
Funny I'm a holster-maker and promoting them, huh? But I wear their class B uniform pants on duty, and carry my back-up in a holster of my own making this way, velcroed in place inside the cargo pocket.
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