I would contact
Mesa Boogie, its most likely a special design Eminence speaker. So even if we figured out what it resembles to a off the shelf speaker. It wont match the other 3
needs to be a matching special design.
of similar interest found a
recone of that part number,
so buy a new one from Boogie or get the bad one reconed
*edit* actually in the pic it looks like a EV speaker
I think its called a PowerHouse 150 which is a 150watt 8ohm speaker actual part number is 761046