I had a Ruger K77/22-RMP which is the all-weather bolt action. Besides being incredibly UGLY, I could never get any acceptable accuracy from this rifle. Like yourself, I very seldom get rid of a rifle. But I did trade this one in for a used Savage/Anschutz 141M. A very happy day in my life. It definitely falls within your accuracy expectations.
These are the only .22 magnums I've ever fired, so I can't offer any first hand experience with others. The Winchester 9422M is a nice looking rifle, but being a lever action, I doubt the accuracy would be what you want.
I have three CZ 452's; all .22LR. Pretty accurate. Think the CZ would in .22mag would be a shooter as well.
I'm not a Marlin bolt action fan, but they do seem to have a good reputation. Supposedly they come from the factory with lousy triggers. But you could get a Marlin and replace the trigger with a Rifle Basix trigger (about $70.) and still be under your $500 limit.
Good Luck. And WELCOME to Graybeard Outdoors