Although my primary recording interest is places and environments, when using the 121, I have been in more close up indoor situations and wondered if I could UP the quality without the size?
Your description is a bit hazy when it comes to what kind of situations you actually need the stxxlth for.
Is it for loud music, acoustic music, recording voice/conversations...?
If you intend to tape music, an SPS mic is not ideal, as others mentioned. But if you only record ambient sounds or speech you might not care for stereo separation?
Some of the mics others here suggested aren't really stealthy at all.
You intend to rely the internal preamp of the HHB recorder?
I'm not sure how much gain it provides, but you might consider shopping for an external pre at the same time. The Church combo has been mentioned...