I do not know of sources for brass wire, but may I ask why you prefer brass over copper? Is it for strength?

The reason I ask is because I recently read a book about trapping, and the author, an accomplished trapper, often used strands taken from a copper appliance wire for his snares.

I have some uninsulated copper wire that is similar to extension cord wire. I will test the strength of single and multiple strands and let you know what I find out. It could save us both some money.