Ithaca used to make a Military and Police model with an extended mag tube (7+1). It was a full lengrh tube, not a screw on extension. I have one, though it is the Model 87, made by Ithaca Aquisition, the company that took over Ithaca Arms in 1987 (hence the model name) when it went into bankruptcy...somewhere along the line Ithaca Aquisition became Ithaca Arms again, and they reverted to the old model nomenclature, i.e. model '37. They are fully interchangeable.
It's my favorite shotgun with the exception of a poorly designed stock, the grip's curve is too shallow and straight.
Funny thing, until a year ago you could order replacement parts for the M&P model, including the extended magazine, now even those are gone. I don't know if it was a PC decision or a stright business decision based on low demand...nevertheless I was PO'd as these parts were taken off their list the very week I had decided to order them...
