Makani fins have a great selection. They are from Canada and are on your doorstep usually only 3 days after ordering.I am a huge fan as they are about half the price of the other brands so you can get one for each board. www.makanifins.com
For Budgi or Canton you need a high rake weed fin ( 45 degrees or more) or a delta/Kestrel fin. They don't work too well with chop or very large boards..Ask Mick he might have something (www.seabreeze.com.au/Members/Profile/Details.aspx?member=Mehore), or try windsurfingshop.com.au - Gareth is based in Macquarie lake.
I met a couple of super nice guys at Green Point this arvo and they gave me Garret's details, will be picking up a delta tomorrow which should get me out on the water.
