I'm not sure anyone here will have all those specs on the Xc shocks...however you do. Just have to remove one front and one rear, remove the spring and measure center of the "Is" extended and compressed, "I" diameter and width. Then you can get the spring length uncompressed, it's inside and outside diameters and it's wire size. The rates will be tough without some compression equipment though.
I know both Bandit and Elka would be happy to custom build a set for you however like you said...that won't be cheap. However if you ride a lot...and hard, it may well be worth it.