Dear Carl,
The first plastic clarinet mouthpiece I made was labeled "Junior",(I'm assuming this is plastic),but the logo I have used on all hard rubber pieces is the familiar MORGAN across
a wreath. When I decided on the finished format I had a die made to read, "MORGAN, and
with the word "PROTONE'" below that. I did not use the word, "PRO" on my mouthpieces.
Neither have I used numbers to designate tip openings until our new VINTAGE line was introduced about 4 years ago. The models were always marked, "RM-06, RM-10, etc..on the hard rubber pieces.
Of course, the tube container would be available in many ways.
Perhaps a bit more research on your part will clarify the situation.
By the way, the interior shape of the throat denotes this is one of RUNYON models, which are made for many customers.
Very sincerely,
Ralph Morgan