I have just been to my local toolshop – Thomas Bros, Holloway Rd, Archway London N19 and they have probably getting on for a couple of hundred lengths of silver steel for £1 a length. The sizes they had were 1/16", 5/64", 3/32", 9/64" and 11/64". Not sure of how many of each. The /64" sizes seem not to be common or even obtainable now. If someone wanted these and was in north London it could be a useful contact. I have no connection with the shop except that of a long term customer. I hope this is helpful.
Bob