Don, try "Theraband" tubing. I made my own wingers which are about 40" high and used the silver tubing, Bumpers go 30+ yards. dokkens about 25 and duck a little less. I stretch them to about 350 %. Real nice arc. I got 100 feet delevered to my house for about $60. You can buy smaller amount just to try it. At 50 cents a foot its worth a try. I got it from these guys.
I purchased 100ft of the grey thera-band tubing to replace the tubing on my GU wingers. I've been using it now for about 2 months and it throws the birds exactly like the original tubing and still looks brand new. Purchased it off e-bay for around 60 bucks.