You are probably looking at $150 for just the limbs but that is not the biggest problem. Most of the models I remember that were offered in both limb styles also were of different axle to axle lengths. Which would probably mean also having to purchase a different string/cable. I am trying to remember what year Hoyt shortened the XT2000 limbs as well but it escapes me at the moment. This could also be a factor.

In my opinion, considering the original cost of the Magnatec ZR200, such a change as what you are suggesting would be cost prohibitive. You would probably be better off just selling the bow on Ebay and buying a new one with XT2000 limbs.