Why do you want a pressurized single?
Experiences I have had with 210s are that they are noisy, very noisy. Just not a big fan. Let's see, Mooneys, Malibus, and Bonanzas with decent times on them are all possibly out of the area of price you are trying to stay in (now that I have typed that, why didn't I just say budget?).
Mooney only produced one pressurized aircraft, the M22 Mustang. There were not many built (19 registered with FAA) and although it's kind of a unique aircraft, probably not something I would buy.
I've never heard of a pressurized Bonanza. There was a Pressurized Baron but they are not very common, representing less than 10% of all Barons.
P210 is the most common and you can get them in your price range (including anx head sets). I don't think the pressurization system is extremely complicated or costly to maintain. However, it is one more thing to go wrong and thus cost money on an aircraft that is at least 25 years old.