I don't know if "Perazzi" refers to the tubes as "generation or type", just what gun they are for. You can forget about the first ones they made, as they are rare enough that you likely don't have that gun, and anyone who has the chokes wouldn't sell them anyway.
Just give as much description as you can on the gun type (TM1, TMS, MT6, MX3 etc.), Top thread or bottom thread. Some one here is sure to help. And yes, the Briley 2nd gen per. is what you need.