Ryton Arms in Thetford
They mainly sell deacs but if your after k98's, Mosin Nagants and such they will sell them on prior to deactivation and you will struggle to beat them on price. Very helpful and friendly people and if you go there to pick stuff up then you have to have a look round their workshop as it is literally floor to ceiling in guns from MG42's down to skorpion smg's- without a doubt the coolest room of guns I have ever been in