I have two suggestions:
1. Go to Ebay and buy a replacement cover (they're very cheap).
2. On Ebay, buy an old (non-working) 180 or 180g and cannibalize it.
You can easily replace the cover by yourself (I've done it - twice!). For some instructions, go to
http://palmtops.about.com/b/a/121024...eo+180+battery
One thing I advise you is to make sure that you disassemble the phone very slowly and over a large bowl or a light-colored cloth made of velvet or some other "clingy"material that won't let the tiny screws roll around.
You will need one of those tiny phillips head screw drivers (they come in sets for working on computers). I think they might also come in those sets for working on eye-glasses.
Before you start, take a close look at your phone. Study everythng, and (preferably) take pictures of each stage.
There is one very short little metal roll (about .2 cm in diameter and about 1 cm long) that always falls out and often gets lost. This little bar belongs in the top left of the phone and you have to put it back before you close up.
It really is easy and it takes about 10 minutes.
Anthea