You can get some great varieties of Saskatoon from the agroforestry research trust - Ballerina is my favourite. With Blueberries varieties like Jersey haven't done well up here. Bluecrop and Duke are the best in my opinion (we have about 8 varieties)
Duke has been coming up a couple of times when I have asked people, fellow goatkeeper in Northumbria has also got Northland, Dixi, Goldtraube and Bluegold - all doing well.
Spoke to Scotplants but they are not taking any orders until April and the lady was very quick to get me off the phone, so couldn't ask for advice on varieties.. But I like that they grow them in Scotland, so seem to be the best place to buy.