Depends on what you want to call "decent". if you mean good enough so that other people hear you, plenty of cheap desktop and lapel mics. If you prefer a small head mounted boom type, the ModMic is just a bit above your price range, or you can get something like http/www.bhphotovideo.com/c/product/1011798-REG/pyle_pro_plm31_cardioid_condenser_headset_microphone.html and turn it into a mod-mic like device with some 3M tape.
Depends on what you want to call "decent". if you mean good enough so that other people hear you, plenty of cheap desktop and lapel mics. If you prefer a small head mounted boom type, the ModMic is just a bit above your price range, or you can get something like http/www.bhphotovideo.com/c/product/1011798-REG/pyle_pro_plm31_cardioid_condenser_headset_microphone.html and turn it into a mod-mic like device with some 3M tape.