Where in GA are you? We're in Atlanta and we have a couple 14.5" rolls of our glossy air-release vinyl laying around. I'll give you the vinyl for free.
You could print the "caution tape" 12.5" wide w/o a border. Then use a chop-saw to trim it down to 12" wide. Viola, you're done.
Call me if you're interested, (404) 228-6329 x3.