I am NOT a holster expert and I don't have a large assortment of them, but one possibility that comes to mind is a Remora (or maybe the similar Sticky). Remoras are secure if the waistband is reasonably snug, but they are thicker than some other pocket holsters. But they can be used both ways especially with the 642.

 

I use a Desantis Clip Grip and a cheap Uncle Mikes pocket holster without any clip (to cover the trigger and keep lint and sweat out). It is as secure as your belt is tight. This IMO cannot be beat.

DeSantis Gunhide Clip Grip Right Hand S&W Round Butt J-Frame Polymer

The DeSantis Clip Grip is designed to fit round butt J-Frame revolvers only. It is built of a glass reinforced engineering grade polymer that's almost...

www.midwayusa.com

The DS clip grip is discontinued, I think, so you might should get one while there are some left.

 

hamre forge grips makes a similar hook grip.

 

Combo holsters are usually not good holsters.
Save your money and buy quality holsters specific for the application.

 

Yes!…the sticky holster….its awesome

there is a reason why it’s popular with athletic people

I can wear gym shorts and the draw string is enough to keep the holster secured onto my body. Plus the material is grippy for pocket carry

 

I use a desantis nemesis for a pocket holster. It would function IWB being held in place by friction but I would recommend a belt holster with a clip.

 

I use the Remora with the removable clip.

 

I have Sticky Holsters for my G43, Hellcat and 642 that I go back and forth with between pocket 330 with no issues.

 

I pocket carry a lightweight snub, either a S&W 442 .38 or an LCR .32.

I installed a Desantis Clip Grip on the 442. I pocket carry it when I wear Levi's jeans, clipped to the top seam of my right front pocket. The entire grip sticks out of the pocket but an untucked shirt conceals it well. The gun also stays securely in place, without moving. It's also very comfortable - I don't notice it. Unfortunately Desantis discontinued its Clip Grip. Hamre Forge makes a Hook Grip, with a similar "clip" on it. Both the Desantis and Hamre Forge clip grips are designed to tuck inside a waistband without a holster, therefore you can easily switch from pocket carry to "AIWB" without anything else.

Most of the time I wear Duluth Flex Fire Hose cargo shorts and cargo pants. They have a small pocket inside the right front pocket that fits the LCR's muzzle perfectly and I don't need a pocket holster. It stays put and doesn't move around inside my pocket. I've been pocket carrying an LCR this way for the past 2 years and I'm very satisfied with this setup. My LCR is fitted with Hamre Forge Boot Grips (without the hook).

Good luck finding something that works for you.

 

If there is a good one, I haven't seen it.

Instead, I switch holsters back and forth between 2 specific ones, frequently with my 642.

For belt carry, I use a smooth IWB kydex hard holster.

For pocket carry, I use a dedicated soft nylon holster with a sticky textured exterior.

Two very different designs.