Swif if you go to a new wheelset and make it modern it will be 130mm spacing, but your bike is 126mm so you will have to stretch your rear triangle or cold set it. Neither are a big deal but can take time (cold setting) or be a hassle (stretching every time you take the wheel off). Also you will be running a cassette with less spacing so will need a smaller chain, this means you also need to change the crank or you will drop your chain between the large and small ring, which would entail a new bottom bracket also. By the time all is said and done you won't worry how much FD's and RD's cost.

Honestly if you are serious about this it should be a one time deal where you find the parts you need in the correct threading and once you have everything take it into your LBS and have them redo it all at once.