This will be the engine I will drop in my Dart when I get the funds.
http://www.forabodiesonly.com/mopar/showthread.php?t=216632
I have purchased a set of RHS heads and valve from Mike in the past with no problems, very good service.
Remember on top of shipping from the states you will be required to pay 10% GST & 5% import duty based on the purchase price.
My shipper quoted $450.00 aus to ship from Cali to Perth.