And a good morning to you sirs.
I have a M2-type tripod marked:
CAL 30 MG L2A1
I presume that means S/N 356, Royal Ordnance Factory Leeds, mfg. 1957
Also presume, given the 1957 date, it was used for the Brit L3A4 (1919a4).
Since it predates adoption of the L7A1...