I am getting a quote to replace my flopper-stopper rig (old one is 4-inch spinnaker poles which is heavy and the outboard end fitting is really klugey for rigging). Fabricator is in Ensenada MX though prices for metal work are not incredibly cheap even there, but quality is pretty high as they use US-sourced steel and they have decent metal workers due to presence of off-road racing heritage (Baja 1000, etc.). I've decided on 10-foot poles for Weebles, but there's no reason you couldn't make them longer for a W40 if you felt it was needed. Please note, there is absolutely no engineering implied in the attached, just my best thinking based on experience.
NOTE - these are for at-anchor use only. They are NOT paravanes for use underway.
Would anyone be interested in a setup for their boat? The end-fittings would be easily shipped, so you would have to source the 2-inch aluminum poles locally. You would also have to figure out the rigging, and of course get some sort of plates for the actual flopper stopper. But the hard part - the poles and fittings - is done. If I had to guess, I'd say the fittings alone would be in the $1K-$1.5K range, but that's only a guess (hopefully high). I'll update when I know more, but give it some thought.
1970 Willard 36 Sedan Hull #40