I sort of ran into the same problem with with DeLorme PN-40. You just can't find a case for it to clip to a shoulder harness, pack or belt. You can lanyard but...meh, it makes a heavy necklace. I tried office supplie stores, hardware stores, phone outlets, electronic stores, outdoor stores. Nothing that fit the PN-40 and could be carried outdoors.

I ended up at a military surplus store and got a MOLLE compatible radio case. Perfect. Fit is adjustable and I can attach it to anything.