Just bought a leather slip case for my Pearl on Ebay for reasonable amount of money. The seller is in Hong Kong and it took about a week to get to Australia. He will sell to the world as well.
eBay Australia: Vert Leather Case for BlackBerry 8100/8100g Pearl phone (item 220107510391, end time 09-May-07 14:17:02 AEST)
-Matt