Hammer67
Professional
Helicon-Tex Foxtrot mk 2 belt rig. Probably bigger than your thinking but they are rugged and carry lots of essentials
I think he was looking for something a little more low-key than that.
Eberlestock also makes a good one. I use it on occasion when IWB isn't practical for one reason or another, although it's not my preferred way to carry:
Bando Bag
Like an ammunition Bandolier, the Bando Bag is a lightweight and convenient way to transport your EDC items. A full-zip back pocket on the Bando measures 5.25”H x 9.25”W x 3”D, large enough to secure most sub-compact and compact sidearms like the Glock-19 and those similar in size. The main...
eberlestock.com
The rear pocket of the Bando has hook and loop backing, which allows you to use something like this, for a little more retention/stability: