Partly wood, partly steel --
Minimal welding:
have your welder fabricate just the end braces as shown at right, and do the rest with wood 2x6’s for the landing platforms and 2x4’s for the long 9’ base. Pre-drill all holes in the end brace before welding.
Do it all yourself --
Simply build two landing platforms with three 2x6 joists (one across the middle) -- then prop them up on something -- be creative ???