I would look at a good quality leather belt and try a leather holster from Don Hume and/or Jason Winnie. They list them under concealment holsters, look at the OWB models. I use Jason's Open Top Pancake w/ Body Shield J111 with a Crossbreed leather belt. Crossbreed also offers some OWB models, I would love to try the SnapSlide.
Another option would be to use a Blackhawk Serpa or Kydex OWB holsters, I carry my XD SC in a Serpa and really like the retention lock and release. The Blade-Tech models get great reviews also, been wanting to try the Partial Eclipse model (last link below).
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