Just a little "heads-up" for anyone in the market for the stock style petrol cap.
There's this one on ebay right now
http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&category=32058&item=4561934809&rd=1
starting at $8:95 plus $4:50 postage
or you can do as I have and get down to your nearest Auto Store and pickup one that is brand new for about $12.