Not quite my gun . . . but darned near a twin, except mine was marked Miroku and not My Luck. About all I can tell you, other than you have a very good, solid, basic double, is that anything marked My Luck is older than stuff marked Miroku. Miroku, in fact, is the Japanese-ized version of "My Luck". They changed the name when they found that My Luck didn't go over very well. But I don't know when the name was changed. One catalog I have, dating from 1964, lists Miroku under that name--which would lead me to guess they made the change from My Luck some time before that.
Miroku-made guns--a lot more over and unders than sxs--were imported to the States under the Charles Daly name. But that stopped over 30 years ago, when Browning struck a deal with Miroku to make side by sides (the BSS) and OU's (Citori) for them. But even the Browning sxs have been out of production for a long time. Parts . . . quite possible you'll never need any. But if something like a spring breaks, unless you find a gunsmith who has parts on hand for either BSS or Daly doubles--and assuming the part would interchange--you'd probably end up needing the part made from scratch. Most likely would be a spring, and they're not outrageously expensive to make.
Like Ted said, wish I'd never parted company with my Model M. Never had any problems with it.
