I opted for a factory replacement from SIG Sauer. After looking at the online store, I called the shop to ask a couple questions. The guy on the phone was friendly and very helpful. After I thanked him for the info he offered to get me a better price than what was posted online, so I ordered right then and there; for 15% off!
The barrel dropped right in and I ran over to the range to put 100 error-free rounds through it — and it still shoots more accurately than me. I was also struck how different the gun looks with a black barrel rather than a worn silver one. As long as the slide and frame continue to hold out, I expect to continue shooting this gun for a long time.