It is almost certainly a forgery and a common forge style seen on eBay in the past.
There are a number of issues with it, but the almost perfectly vertical strokes in the loop under the Ms is a dead giveaway.
Here is an image from the Operation Bullpen book site. You can see the similarities in the strokes of the M:
And, if it came through Angelo Marino... that in and of itself is enough to be certain it is a fake.
Sorry.
