Can anyone tell me about these? I just picked one up in a pawnshop yesterday with a Weaver scope on it. It has the original sights (strange array of front sights). It's a little loose in the stock, but that's easy enough to fix. There's no serial number on it. Any guesses as to age? I'm also curious about what the (a) means after the model and how it differs from other 46B rifles.