Obsolete? Hardly. On page 18 of the Bowers catalog you'll see "CAC Series Silencer Retrofits". I had my CAC-9 upgraded and now I have the latest Vers stack and inserts for a M11/9, M11-A1, UZI, and all Lage uppers. Plus lifetime service and cleaning for only $20 return postage.
Interesting info. I have a Bowers CAC 9mm in the mid-5500 serial number range, bought in early 2011. It has the adapter for different threads. Is there a retrofit for the baffles which Tom recommends? I had not heard this previously.
Also, while it may be discontinued, they are still out there for sale new, as well as the VERS 9.
http://www.silencershop.com/silencers/pistol/bowers-cac9-subgun-suppressor.html
http://www.silencershop.com/bowers-vers-9s.html
I too have been waiting for a 3 lug. They say they are going to make it.
Look and see if the baffles have the scallop cut or "dish" coming off of the center of the baffle. If so, then it is the newest stack
Looking down the front of the muzzle with a flashlight, it appears that the last/end baffle is 'dished', or funnel-shaped. It is symmetrical and round, though. Is that what you mean? Thanks for the tip.