I would not be surprised if clubs would ban MHz radios because it would make administration of a race meeting much easier - you don't have to worry about who is on what frequency etc.
If you are happy with wheel type transmitters, you can get 2.4GHz radio gear laughably cheaply - less than £20 (so AU$30-40) from sites like Hobbyking.
e.g.
www.hobbyking.c...ttery.html
Receivers are pennies too.
Stick type radios are more difficult, but still available.
