Before you look at holsters, you need to check your belt. Get a belt with some stiffness that will support your holster. That will make more of a difference than the holster. I like the Wilderness Tactical Frequent Flyer 5-Stitch Belt.
Also, have you considered wearing suspenders? I have the no-hip-no-ass problem, too. Wearing Perry Ubee Suspenders under my shirt has made a huge difference.
+1 for Rgrizzleleather.com.I buy and use custom leather holsters made by guys like Ryan at R Grizzle, and Andrews Holsters.
I have never tried them on prior, basically bought them thru word of mouth. I have lucked out, I like them a lot.
But it can be a crap shoot. Like many others, I have a drawer filled with holsters.