Stymie,
Any action that has a .473 bolt face would be a good choice. The 98 Mauser actions are a very good design, but alot of the later war time actions where not made with good steel and are weak. The best Mauser action for the money on the market are the CZ action today. You should be able to pick up the whole rifle for $75 to $80 if you get one that has a good action but the rest of the gun is rough.