Do you want a single or dual preamp? Digital or analog? That makes a big ole difference in price as well as quality.
My setup for vocal recordings includes a trio of AKG D5s, an Heil Sound PR35s, as well as (my personal favorite) the Audio-Technica AT4050.
The AKGs were about $160 in a three pack I found online, the Heil Sound was about $230 at the local music store, and the Audio-Technica AT4050 was given to me as a gift, but it will run you close to $600 retail I believe.
My preamp is a rackmounted ART but that's well out of your price range, however, ART also makes a much smaller standalone version that retails right at $30. I can't vouch for that particular product, although ART is a great brand and has never let me down.