68 Fury rear drums source or options

I've got a 68 Sport Fury w/318 and drums all the way around. I've completely rebuilt the fronts, new drums, shoes, etc. I am having no luck locating rear drums. The drums at 11"x2.5", but the shoes are 2", so perhaps they are considered 11"x2". Regardless, I cannot find any drums for this car. Has anyone already been through this and has a solution for me?

Thanks so much!

- Walter
1968 Sport Fury