Hello,
I bought 2 kilos of 95/5 mix from the Pewter Sheet Company yesterday. £30.00. I am only a 10 minute drive from them and collection was no problem. The pair are very helpful, but did say that they keep very little stock, so they need to have a couple of days notice if you intend to collect, so that they can make up the order for you. You need to talk to them about the most suitable mix of pewter for your needs, if you're after casting stock. They will make up whatever mix you require and will advise you if you're not sure. What appears on their website is only part of what they produce.
A word about their website: they are having trouble with it, and some parts of it are well out of date. The contact email page doesn't work, so you're better off phoning them.
Regards all,
Greg Miller.