We do know it is a liquor bottle of some kind, whiskey, vodka, etc. and it probably dates from the 1950s or early 60s.
The MG mark on the base appears to be the mark of Maywood Glass Co of Compton, CA which became an Anchor Hocking plant in 1961
The R[ectifier]-76 mark gives a clue to the product if one can match the # to a bottle with a label....