A2, A3, and A5 are all part of his range, I would think. Total rainbow on the turn, which takes out most big suited cards that might float the flop.
22, 55, and maybe 77 *might* just flat preflop, flop and turn, but 55 and 77 are almost certainly going to raise at some point. And, of course, 22 isn't calling on the end.
Maybe something like a suited King-rag? I dunno, that's stretching it a little, depending on the villain.
Given that they don't necessarily call a push with an ace, I'd tend to agree with primo that a smaller bet is more likely to get paid by the hands you're beating. But then again, I don't play $550s, and the villains I play can show up here with crap like J3 or QT (yes, I've been called on the river numerous times by queen high or worse at the lower stakes, and last night actually got called on the end by nine high for about 2/3 pot).
So I value bet 100% here, and expect to get called a LOT by worse hands, but that doesn't necessarily translate to the typical $550 villain.