Moosie,
I think you could be very surprised how well you could do making holsters. Like you said you won't quit your day job but there is a large market, 60 million people need them. Maybe buy a decent holster such as Galco or something similar and tear it apart and see how its made. Check out gun broker or ebay and see if you can find a used one for cheap. And definitley check with Sig's guy. While it may seem in the best interest of those of us in the firearms business not to help people do our job, you will be surprised how helpful most of them are.