I know of one reputable seller in the UK, although I'm not sure how to contact him outside of facebook...If you join the
neo group there, they can certainly help put you in contact with him. They can also help you find other european vendors or possibly even work you into a group importation that a couple people in the EU regularly organize.
Other than that, there are private sellers on ebay that have been selling good quality plants in Europe.
However, there are several scammers who operate on ebay in Europe as well, selling intentionally mislabeled Neos, so unless you trust the seller, it's best to only buy plants that you can 100% verify through the photos if you're going to buy on ebay.