WWI leather map or telescope case US Military Ordnance Cartouche marked

Description

I found this a few weekends back at an old military surplus store collecting dust behind the counter.  At the time I wasn't sure exactly what it was used for but have since learned that it is believed to be a US Military leather map or telescope case from WWI or WWII era.  It has the following stamped into the leather:
US Ordnance cartouche with a "6" in the middle
"T-37"
"A" in a box
I couldn't locate any other stamps or markings. Appears to be very well made.  Measures 30" long, 3 5/8" wide and 2 high."
Condition:
Overall good condition.  All leather intact and not deteriorated.  Carry strap and leather clasp in very good condition.  Has v
arious
scratches
and marks with some cracking on each side of case near opening (see pics).
Bottom part of case has came partially unstitched but could be repaired very easy or left as is.
Appears to have eight holes were other rivets may have once been in place but are now missing.