Best price I found was thru my small town local Ace hardware, where I am a long time customer.
1/2" 19ga GAW x 48" x 100' was $105.
There was no shipping charge because it came in on their regular weekly order.
Finish gun on the side of 2x6 with plywood nailed over it to cover edge. Bottom is wrapped around treated 2x4 stapled finish gun. Gonna lay bricks in a trench and pour concrete around last