After doing some research, the original materials I had intended on using will not work (66061-T6). I've put in a few inquiries about custom sized materials (6061-T4).
In the interim, I did some looking for alternatives to aluminum. As it would turn out, if built from 4130 A519 chromoly, the weight will end up basically identical to Aluminum because wall thickness can be much lower and still maintain high strength. It's also about 1/2 the price of the 6061-T6 I've found, but I need T4, not T6 so not sure how the lower temper will change the material cost.
My original intent was weight savings, so if I can achieve my goal using 4130, and end up with the same weight in the end I may go that route. We'll see soon when the companies respond with their quotes.