Thanks for the reply.
I will just add that I have a large collection of 4x5 negatives and still own a 4x5 camera, so I will be printing from those as well as digital negs. I hope therefore that this thread will not be deleted
I just ordered the cyanotype kit from Silverprint which I believe has some sheets of Arches Platine paper and some digital film to try out. It would still be useful to know what papers are available in the UK that can be used with these processes without breaking the bank.