Wishful thinking I think it is 98306 around a district stamp I or 983106 with the 8 upside down and 6 used upsidedown for the 9
The number IMO is a "983106" because there is no mistaking the orientation of the "3", and I don't see the "1" as a district stamp. With the "9" and "6" at first looking to me like a "6" or "9" stamp that had been inverted. But then after a little closer look - it looks like it might be some kind of engraving (?). Because the enclosed center part of the "9" has more of a round shape, while the "6" is more egg shaped. FP
