I think the cost of the replacement part purchased directly from Elektron will be minimal, the amount of effort to replace it will not be insignificant though. If something heavy enough to break the screen fell on it and with such precision that the tiny little screen bore the brunt of the fall, I’d be a little concerned about overall functionality of the device or wonky encoders, but if you or someone you know has the skill to do the screen swap it might be worth it.
Soldering a ribbon cable is not like soldering wires on a guitar pot, it’s much easier to damage the components or the cable. I’d make the decision based on whether or not you’re willing to risk losing the 100 you’ll probably spend for the machine, parts and supplies just in case the thing doesn’t work right or something gets damaged in the process of installation.
On the other hand, if you spend 100 and get it in working order then the price may be worth the hassle, but just consider that if you can find a deal on a perfect M:C for 200 at some point in the near future, is it worth the extra money to you to get something you know has never been damaged and already works?
If you plan to use this heavily as a part of your current set up then that’s something you’ll want to factor in.