Used AI Nano isn't a bad idea if you can get it cheap enough. The Nanobox gets a lot of press in the nano world as a great light, but I haven't seen it. Then there's the Kessil A160. I'd lean that way because I'm very happy with my A350s. honestly, if you wanted the head room, you could get an A350 and just dial it back. They're still available from a few stores for $250. Innovative Grow Solutions is, I think, the name of the place that has them.
Of the lights I listed, the AI Nano is at the bottom. I have one, it's not bad, but there are better lights out there.