Once you know the brand of the driveshaft hopefully you can "sweet talk" the distributor into selling just the adapter. Hope this helps. What material is your driveshaft made of, what cv/universal joint does it use? Does it have any markings on it? The more info you give us the better we can help.
"I drive a race truck, look at how loud I'm going!" -Me " I've seen Zs that I wouldn't touch w. BigTDogs d!ck"-Bernie