Hi - ordinarily I wouldn't comment on such material since my knowledge of Scottish glass could be written on the back of a rather small postage stamp, but …………….
just for the sake of helping, possibly, can tell you that in the second part of the sale of the Michael Parkington collection, disposed of thru Christie's back in 1998, this oversized egg-cup shape in some sort of dusky blueish shade, and with masses of irregular large bubbles - was catalogued as a 'Monart Coupe' shape JB.
Unfortunately, the catalogue description omitted any reference to a colour code, but does indicate height at 22 cms - it also appears to avoid any indication of age.
If the damage wasn't mentioned by the seller, then perhaps best to get a refund - would imagine that from a collectors point of view, and unless of mega rarity, then this one will have little commercial value.
anyway hope the above tit-bits of info of some use.