I have a mouthpiece that is a mystery!

[Santandad1214]

Mystery vintage tuba mouthpiece - help identifying
I found this mouthpiece about 2010 in a Community College detachable-bell King sousaphone case. The sousaphone appears to date from the mid-20th century and was stored in one of the old plywood cases with the bell recess.
The mouthpiece has:
No maker's marks or engraving anywhere.
One-piece construction.
Standard American tuba shank (fits modern Wessex receiver normally).
Deep funnel cup.
Very wide rounded rim.
Approximate inner rim diameter around 33–34 mm.
Appears to be lacquered brass (possibly—not certain).
I currently use it alongside a Canadian Brass MB-88. Interestingly, despite the deep funnel cup, it plays very securely in the upper register and is my preferred solo mouthpiece.
Has anyone seen this profile before?

[bloke]

My wild guess is that it's a Reynolds "Dr Young" mouthpiece that someone unartfully altered on the outside.

[tubanh84]

My wild guess is that it's a Reynolds "Dr Young" mouthpiece that someone unartfully altered on the outside.

That was my first thought, but I'm not a machinist. Do you think the three "stripes" on it are lathe marks? I've never seen a Dr. Young mouthpiece up close, so I don't have a sense of how much material there would be available to remove.