[Harp-L] Numbers on MB plates ?

[Buck Worley <boogalloo@xxxxxxx>]

List,
I found a box with a couple dozen old used harps that looked repairable on the surface. Assorted standard Marine Bands, 3 old type Old Standbys, a couple of Huangs and 2 Vest Pocket harps. I picked 6 MBs and began my restoration project.
Two of the MBs have numbers stamped on the plates. C harp, top plate has 0797, bottom plate has 0397.
D harp, top and bottom plates have 1106 stamped. On the bottom plate the #8 reed has red paint?? on about 2/3 the lenght of the reed. Also, the reeds on this harp have a copper tint.
A long time ago while at the NAMM show, the Hohner rep gave me 3 or 4 prototypes to try out and provide feedback which I did. I just wonder if these may be prototypes.
I have never noticed anything stamped on reed plates before and never seen red reeds or copper colored reeds on a Marine Band. There were no other markings that I found.
I'm just curious. Can anyone tell me what these are?
Regards,Buck