Yep, McMaster-Carr is a good source for wire, lip materials, etc - fast service, good prices. I've used soft temper brass wire which I understand is the traditional wire once used in Bagley baits. But I really prefer the soft temper stainless "safety wire" that you can also buy at McMaster. It's just slightly more stiff than soft brass and it will never corrode like brass or copper. Like Ben, I also go with the .040" diameter, which is a good match to the wire originally used. I go to .032" wire for very small baits less than 2" long.