I have a model 930 SPX (pistol grip version). This evening, I disassembled it for basic maintenance; and while reassembling it, the magazine spring got away from me. Not a problem that it got away from me, except that when it did, there’s a little white plastic mushroom-shaped "plug" that fits into the muzzle end of the magazine spring, presumably as a buffer between the end of the spring and the inside of the magazine extension, that got launched into low earth orbit, and I can’t find it anywhere. I reassembled the gun without that white plastic plug, so that the spring is now in direct contact with the inside of the magazine extension. Other than the wearing of the steel spring on the inside of the end of the extension tube, I can’t imagine that it would interfere with the gun's operation. But, I’d prefer to put the thing back together correctly. The problem is that I can’t find that part listed in any of the schematics I’ve seen on either the Mossberg website or in the owner's manual; so I can’t replace it if I don’t find mine. A. Does anyone know if this is a problem? And... B. Does anyone know what this part is called, and where I can find one?