In regards to a recent post in this forum... Where can I find a threaded barrel for my p938?!?

And what can do you think would be best?

I'm pretty sure mine is the thread you're referencing.

The threaded P938 barrel is a factory offering from SIG now.  It seems to be out of stock at SIG, but some dealer might have one.  Right around $200 with a thread protector, and mine dropped right in.

As for the suppressor... the Thompson Machine Poseidon is what is pictured.  Honestly, going any bigger would be, IMHO, a bit silly on such a little gun, but would offer better sound reduction.

http://www.thompsonmachine.net/?page_id=99

Threaded barrels for both 9mm & .22LR are now available direct from SIG. It may take a few weeks to get, but they do show up, eventually. Both of mine dropped right in w/o any additional fitting. Call SIG, be patient, it will happen.