Entitlements would depend on the contract. Normally there would be unused annual leave to be paid, and there would normally be a notice period specified.
Good luck with enforcing clauses in the contract though. If the company doesn't want to pay then you won't have much luck.
All expatriate workers should be aware that they really aren't covered by the Labour Act here.
CCH publishes the PNG Labour Act and they have the following commentary :
"Moreover, it seems that the Employment Act does not apply to non-citizens (Atlas Plant Hire Pty. Ltd. v Beck (1984)"
"...It seems that persons exempted from the provisions of the Act would have to rely on their common law rights (if any).