Certainly not crappy, but sometimes available in your price range:
Charles Daly 500 or Miroku 500. I bought one practically NIB for $550. Open the chokes and you're good to go with 2-3/4" steel loads. If you insist on 3" loads, look for a beater Browning BSS 12 gauge (and make sure you don't head out with M/F chokes). These are fine with steel, although not all feel that way.
My SxS duck gun for 3" steel: Pietro Bernardelli, 12 ga, DT, English grip, splinter, extractors, oil finished wood. New about 3 yrs ago at $375 (closeout). You will pay more now for a used one, but it's a very decent gun, made in Italy (not Turkey). Also available with PG, ST, beavertail if you look around. A fine gun for the money.
