Just a thought...
I wonder if a person were to purchase a spool of lead wire, and simply cut several lengths, how that would work? One other option would be to figure out what length you would need or want and use a pair of pliers or diagonal cutters to indent the wire, then role it back on the spool for ease of carry and use. Then all you would need to do is unroll a section and bend to break it off...hey, forget everything I just said, wacth your local retail fly shop shelves for a new, innovative product :O)
"Fly-fishing has many attributes, but none more pleasing than it's ability to liberate the young boy that still hides within me and to let that boy live again without embarrassment or regret, sorrow or anguish." Harry Middleton