TeeDee or I would, but what rope we have is pretty much committed to Bridges and buying enough for 1 or 2 or 3 or ... whoopie sling setups makes the S&H costs on getting it here and then to you as much as the rope almost. Not economic.

Also, as Frawg pointed out, attaching the sling to the hammock is going to be pretty much your task and would be as difficult as making the slings in the first place, i.e., not very difficult at all.

If ZA206 is doing the splicing as a business, then he would be set-up to do it already and Frawg's suggestion is probably the best way to go if you really just want to buy.