Maybe this will jog your memory:
Possibly:
Ulman (with a flourish or two; the top arc of the "a" is missing)
77 (this date is certainly 30+ years old)
1 or
I (grading system, style number, or serial number?)
Or is it Hebrew (or some other non-Roman characters)?
Is this a pipe, or perhaps the only pipe, from a long-forgotten artisan or hobbyist pipe maker?
Inverted. I'm not sure what it is.
Images converted to monochrome, cropped, increased contrast & applied an
unsharp mask filter.