for getting hold of a conversion, keep your eyes peeled on here and then just get it freighted up. i picked up a T5 with all associatde s**t and bits and had it freighted to Townsville for $650.
as for install, i have no suggestions as i did mine my self. get you and some mates, a week, a carton or three and get stuck into it. use the doco on here for instructions
if you cant do that, leigh holman is a good bloke, but i dont know if he does that level of work. another good bloke in cairns is Danny West on english street (i think, the one between anderson and hoare st). I always used to go to him and he is the only mechanic i have ever trusted with my car and to give me straight advice, good bloke danny.