The Ruger MkII and the Browning Buckmark are the two most popular current production .22 pistols.
The Ruger has the reputation for being able to digest any ammo, while the Browning is good, it does have some issues with certain types of rimfire ammo.
The Ruger has a ton of after market performance parts, far more than any other brand, the Browning is a distant second in this category.
The Ruger is a pain in rear to field strip, and the Browning requires a tool.
Both can be found in 95% + plus condition on the used market for $300 or less for the base models.
Both also come in high end target versions
Other new production 22s I know nothing about.

Beretta Neo
Browning 1911/22
Walther P22
Ruger SR22
You might want to consider a older Hi Standard though they tend to be a bit more ammo sensitive than the newer offerings, they are easy to field strip without the use of tools. Nice 90% condition base models are in the $300 ballpark and the high end target versions cost more.
Up the food chain is the S&W Model 41, Hammerli SP20, and Beretta 87
