Fine silver square tubing

Hello, Does anybody know where I can obtain fine silver tubing of the
square variety? A variety of internal and external diameters would be
the best, but otherwiser something around a 3mm OD will suffice. It
has to be fine silver and not sterling …

Thanks to one and all,
Sadie

some times ago i had to make square cross section tube my self, the
only problem was after 3- 4 times drawing ,it starts to bend , any
idea how to over come that?