Does anybody out there have any clues as to where to obtain/find ammo for this old and obsolete round. My dad has an old Drillings combo gun with side by side 16 gauge bores over a 7 X 72R rifled barrel. He has only about 3 shells and we were going to put a few rounds through it. It is in excellent shape but has been previously fired so would not be spoiled by a few rounds. any help would be appreciated. I have already asked this on shooters.com and a few other sites. Any suggestions?