Engine,318/360

Hey guys I'm in the market for a used engine as in the size I have posted. I believe the Chrysler engine is the best way for me to go. Unfortunately I'm not able to pick-up from living in Australia. But surely shipping would be an alternative transport. I have noticed on some for sale ads, that they will not ship. Now that makes it a bit hard. Is there a reason for this ? Curious.
360 would be good. Plenty of torque. Any help and responses would be appreciated.
Thanx Guys