You need to follow MUTCD Standards, VDOT requires .1" Alum, you can get away with .080 around here. PM me if you need assistance in the setup of the file or have questions. also need to have the Highway Gothic Series Font. If you need a post you want to get 2" Breakaway punch post with a install sleeve (Harbor Sales out of MD has them they deliver to Richmond) i have done lots of highway
signs in the DMV.....you can try Payne
Signs out of Bealeton VA for low qty of 3M sheeting, like High Intinsty or Diamond Grade, Translucent EC.....etc like someone stated it could be expensive to the purchase the approved materials for the DOT. You Also need 1.5" Rond Corners. They are also picky on the border spacing size and all the little details they spec. Although i dont think this project will be the picky, its when your doing new neiborhoods and such where they "inspect" everything.