You can consider having it done by sheet metal shop and it would be fairly inexpensive. They'll probably have a small brake to do it with which is a must, and a good mechanic should be able to get your measurements. The problem is getting both (shall we say) vertical sides equal, which is a feat in itself. You might consider trying to buy some channel. This would be a much better way to go, as the channel would be formed thru a die and not a bend.
The sheet metal shops I have dealt with usually don't carry brass, in which case they will probably let you supply the materials. If a mistake is made tho, thry will more then likely not accept responsibility for the materials. Bending metal exactly as you need is an art unto itself. I know having worked as a sheet metal mechanic. Also consider a front standard off a parts camera.