If you really want an 18rg there is one available from SON
IMPORTS ( I think thats thier name) in Wangara just near my place. I was there saturday. It is not in the best of condition but worth a look. You would have to negotiate a price as I think they want tooo much for it. Around 8 to 9 big ones. If you need to contact them I will look up their address and phone number for you. I have an 18rgu at home but unfortunately it is going in a ra28
Dave