2008 Gt U-joint Is An Endangered Species

I got diagnosed by a local transmission guy, and he told me I need to replace my U-Joint. Problem is, Ford doesn't have the part, and he can't find it; said I'd have to get a DriveLine company to build it from scratch. That would take about 2-3 days, who knows the cost. Anyone have any idea where to find one otherwise, or why this part is extinct?

Thanks, gang!