TXBear and Trent:
I made the plate and cut the rack myself out of Stainless Steel. I can't remember the cost of the steel, but think that it was less than $75 for both plates.
The process was really rather easy except for the fact that I had never worked with Stainless. I found that it is REALLY HARD. The holes have to have carbide bits and the small about of cutting was a challenge, so the time factor was large. If I had the correct tools it would have taken me no time at all.
Someone that fabricates SS would be able to do it quickly. It was fun for me to do, but I would pay a professional if my time were worth anything.
If you wish, I would be willing to send measurements to help you via email.
This thread more than 2 years old. Since then I have refined the system with a couple of different bags that look great and really work well. My favorite is a Saddleman Trunk, the buckles and lines look very similar to my bags