Bob Reeves 41HF Flugelhorn, 42 rim, no step

This is the under part of Bob Reeves' 41HF, likely the deepest model available commercially.
I've included reference photos, but the attached rim can be used with a 42 without any step.
(Rim is not included.)
40 is unverified, and while 43 can be used, it will create a slight step.
The shank is standard.

It's not excessively deep, but rather almost like a French horn. However, the center of the cup is slightly narrowed, showcasing Bob Reeves' signature sense of balance.
It also sounds great when amplified.
In most cases, this is not kept in stock and would require an order.
It is particularly effective with inexpensive flugelhorns.

Since I only use my flugelhorn a few times a year, it has seen little use.
I am selling it because I am downsizing my instruments and the shank no longer fits.

There are linear discolorations on the cup and shank, but this is present on all 20-30 Bob Reeves mouthpieces I own, so I believe it is a result of the plating process.
It does not affect playing in any way.
There are no modifications to the shank.

The rim was attached until I listed it, so there is no corrosion or catching.

Thank you for looking.