Oatley electronics located in Sydney sell rolling code transmitter and receiver kits. I bought them and the work well.
see
www.oatleye.com
I designed and built the garage door controller since the Oatley unit is a receiver (4 channels) only. However it is temporary as I intend to include an overload function one day when time permits. Currently, I have to be careful when closing the door to ensure it does not hit an obstruction - such as the neighbour's cat.
Len