The LCR-22 is the only .22 revolver I would consider under $400. The others in this price range have reliability issues or extremely heavy triggers, The LCR is a good choice if you want to learn how to shoot a lightweight DA revolver, and especially if you are considering a centerfire LCR for carry or home defense.
If you want to stick to S&W, there are the Models 317 and 43c, both lightweight 8-shot .22 revolvers. The 317 has a hammer, the 43c is "hammerless" and DAO. But they will likely cost $500 or more. The good news is there are centerfire J-frames for around $350 when you get ready to compliment the rimfire model.