This is not surprising given the slow state of the economy, the high euro-dollar exchange rate, and the leveling-off of interest in Civil War reenacting. Actually, there are quite a few used Civil War repros floating around out there, as old people leave the hobby and new ones enter. Good places to find them are at sutlers at Civil War events, North-South Skirmish Association events, and some of the larger gun shows.
I have to say that the Euroarms muskets are a notch above those made by Armi Sport, but neither is particularly authentic, placed next to an original. The closest repros to the originals were probably the ones made by Miroku of Japan, but those are generally no longer available.