Sourcing holster straps

Hi all,

I recently picked up a Swiss Arms multi angle belt holster that works well with my compact 1911.

I tried my 6" Dan Wesson in it too, and it fits.

Except the retaining strap isn't long enough to go over the butt of the Wesson. (I've one of the smallest 1911s out there, and the strap at its longest only just fits, so it's quite short).

I could rig something up with velcro ties, but I'm wondering if anyone knows of a walk-in place to source a short webbing strap with a side release buckle? To extend the original.

I specify 'walk in' because I tried a couple of similar buckles I have, but they all seem to be designed differently and aren't interconnectable, so blind online buying wouldn't be an option.

The more I think about it, probably handier to rig up something with velcro ties...