There was this query on the road.cc forum, in relation to Zondas...
http://road.cc/content/forum/79032-advice-replacing-rims-please
To save you looking through all the replies, the official UK Campagnolo service centre (who post on here from time to time I recall) replied that
"We can rebuild your Zondas for you.
This is not a job we generally recommend that end-users try to complete themselves as even experienced wheel builders sometimes struggle with G3 wheels and it is quite possible to irretrievably damage the rim in the build process if mistakes are made. In the same way, although we train Campagnolo ProShops in the method and technique, as they do not build these wheels with great frequency, many of them ship the wheels back to us in any case.
If we can re-use the same spokes, needing only rims and nipples, the cost for a pair (depending on the year of your wheels and whether you want 2-way-fit or not, if available for your model year) would be approximately £420.00 - so close to the cost of a new pair of 2 way fit wheels.
Let me know if you wouls like to go ahead and we can calculate an exact cost based on the model year and variation of rim that you have."
This was a couple of years ago, so price might have gone up.
I paid £325 for my Zonda 2-Way Fits, so at that rate I'm almost certainly going to be better off just buying a new set. Eurus rims will no doubt be more expensive.