You don't state whether your CA-11's are the cardioid or omni version. While I agree with Mike B's suggestions of the Countryman and Nevaton mics, they are omni microphones and might require a change to your usual stealth taping techniques if you're used to cardioid mics. It's generally "easier" (and cheaper) to make a very good sounding omni than it is to make a very good sounding cardioid microphone, hence the generally more expensive pricing of very good sounding cardioids. I own sets of the CA-11's and Countryman B3's and have gotten great results while stealthing with both, but they are different tools for different scenarios.
Or, also as Mike suggested, you stick with what you currently have, as a very noticeable improvement in your audio recordings will likely involve a considerable investment. My .02.