There's a reason why ORD doesn't offer a 10 spline doubler..its the same reason you can't buy grenades and old dynamite.
I've purchased a lot of things in my 50 years on this planet and only one time in my life has the CEO of the company ever crawled under my truck, without being asked, in the baking 100 degree sun, on a dirty rocky trail in Moab and completely adjusted the entire shifters/ linkage on my transfer case/doubler so that it worked perfectly, all because 1 rod was rattling a little too much for him. A doubler that he didn't originally install or put together just sold the parts for. Companies that are willing to do that level of customer service will always get my money. Lucky for us this board has quite a few of them.