Get some 50x50x6mm angle iron from that unmentionable place and cut it to suitable lengths and stick it in the bench vice, I folded all of the alloy in the car in my avatar by hand using various makeshift mandrels and jigs.
1.6mm alloy sheet cuts OK with a jigsaw if you use a fine blade and run it at high speed.
Word of warning, make sure you use separate blades and flap wheels for steel and aluminum because the particles become highly combustible when mixed and get hot enough. I don't speak from experience with this advice but know a few guys who do