88 fourwinns sundowner205, 5.7 cobra. new to me 21 footer, replaced engine and upper. upon cleaning prop, can't identify it: ss 15x17, 15 spline, #391290, has a m in a square , for Manufacturer? (michigan wheel it isn't). Problem is, in process of winterizing, took it off. The rubber hub is soft and gooey around the first 1/8 inch of internal hub- spun? And how to identify the prop, in order to get hub? Thanks