< $500
Superlux S241 mics are a good value ($130 each!), although they don't have matched pairs. However the Superlux S502 ORTF is two matched S241 caps in a Schoeps ripoff housing, by all accounts not too bad at all. You can find some A/Bs with the Schoeps MSTC 64G here on tapersection.
Line Audio CM3s and OM1s, both are an outstanding value (about $350/pair with shipping and customs fees) if you can find the importer, he lives in Canada.
$500 - $1000
I have a matched pair Beyerdynamic MC930s that sound really nice, and you can find them for $800. They don't get much attention on TS, but are an outstanding value. I like them almost as much as my Gefell M300s, which cost three times as much.
Oktava MC012's can still be obtained at reasonable prices if you only get the card caps. There are electronic mods (mainly replacing the capacitors) that are supposed to open up the mic
$1000 - $2000
Neumann KM184s are consistently good, about $1800 for a matched pair, but folks seem to either love them or hate them.
$2000 - $3000
Microtech Gefell M300s or SMS2000/M20(card) or M21(hyper) caps are very sensitive, accurate and musical, awesome for taping.
If you have money for more than one pair of mic, I would suggest getting some hypercardoid mics, or even a short shotgun, for bad sounding rooms. Sennheiser MKH8060/8070 mics are really tough to beat here, but are expensive - $3000+ for a pair.
> $3000 Sure you could drop a wad on Schoeps MK4Vs or DPAs, very nice mics, but it's not really necessary!! Too many other things are out of your control for live taping. This is from an an ex-Schoeps taper, used to have some CMC6/MK4s, really nice mics but I got paranoid everytime it threatened to rain. Speaking of which everyone needs some rain mics, see Superlux entry above :-P