Oddly enough, after reading and posting to the thread about finding stuff you forgot you had, I found something I didn't know I had and have no idea how I got it.
A Biancvhi #111 "Cyclone" holster for a Walther 380 Auto.
I don't have any Walther pistols, but I've got a CZ VZOR 70, which has a very similar profile and fits in the holster like it was made for it except for the retention strap being slightly short. With the holster off my belt and using both hands, I can snap it, but I cannot snap it with one hand with either strong side carry or cross-draw.
What's the best way to stretch the strap a scosh without ruining its "Been there - Done that" appearance? (It appears to have been carried a lot and cared for little)
My plan is to open carry the CZ cross-draw while at my favorite range so I won't be effectively unarmed at times while practicing with my concealed carry Tomcat and/or 637. There's never been a problem that I know of, but it is an open to the public outdoor range in the middle of nowhere and I'm not as young as I used to be, so a well worn, evil looking black pistol that few people recognize in a well worn, high quality leather holster might be a good insurance policy.