I was walking through Sakuraya yesterday and I noticed they have Cassiopeia E−65s, the same model I use for only something like 5900 yen which is about $50!!! If you want one now would be a great time.
Note: If you really want one setup to run JWPCE you will also need at least a 32meg CompactFlash card to hold the dictionary. If you want to install the Daily Consice Dictionary you will probably need at least a 64meg card. Those are probably about $50