Bucardo, the company behind these pocket watches that allow you put use the inserts for the bands that let you substitute the top for the cover and the bottom for the chain. For $199 each, it's more than I'm willing to pay for. It's not bad but I feel there could be less expensive options. Unfortunately, there are none after a couple of Web searches months apart.
if anyone knows of other designs and options, please us all of us know. I'm sure there are quite a few who would love this optional use of our Apple Watches.