Like others already stated, don't waist your money coverting an Military action, unless you want a small ring mauser 95/96. You can buy actions from CZ, already to be barreled and stocked to your choice, I would go this route if wanting a 98 Mauser style action today, due to the cost of modifying an Military 98 due to labour costs.
One action not mentioned is the Remington Model 30 AKA Enfield model of 1917, these make great custom actions and only need the trigger changed out, as Remigton already did all the modifications when they built these tough 98 type rifle actions. Have a look at the A-Square rifle co, they use these for all there heavy thumpers!
I built my 35 Whelan a decade ago buy buying a Husky model 1640 commercial 30-06, was a great action to build on! No alteration to the bolt handle or action at all, letting me put money into custom trigger gaurd, saftey ,barrel ,etc.
You can pick up a FN rifle that has been hunted hard as a donar rifle for a reasonable price, make excellent sporting rifles.
Good luck, Dale Z!