gevent runs most of the protocol implementations written on top of standard socket and ssl modules. For example, pure Python mysql-connector works fine with gevent.
I mentioned mysql-connector as an example of a complex enough library that runs with gevent via monkey patching (in reply to "gevent only solves the most simple conversions by monkey patching", which is wrong).
Have you tried gevent-MySQL? It's written in Cython and as far as I know is fast.
There's also a mysql driver for gevent implemented as an extension: http://github.com/mthurlin/gevent-MySQL