I carry my Glock 30 all the time. Mostly IWB, but I also carry OWB occasionally. The Glock OEM holster actually keeps it in tight to my body. With a proper cover garment it still conceals pretty well. YMMV as always.
If your husband has a favorite gun shop, go ask them what he has been looking at.
They probably have an idea of what he's been gravitating to.
If not, ask if they would do a gift certificate.