Now that's an interesting question for which I have no answer.
When I bought it, the fellow selling it figured it was a 58 trim. I don't think such a wheel actually exists. Comparing it to pics I've seen of the 57 trim, 60-1, and 62-1, it looks like a 62-1, from the outside, at least.
I haven't taken it apart to measure the wheel size. Might get around to that one of these days.