The guides will be keen on big tubes, very colourful, orange, yellow. You'll catch fish on large doubles too, Springer did on Ponoi Gold, not terribly big - size 6 I think. You'll be after osenkas, so big and colourful to trigger their aggression. Buying flies there is expensive, but guaranteed to be "right". Anything you'd use on the Tyne would work, but in bigger sizes.