Front drum HELP!!

I lost you too. Yes the 10" front drums are available and cheap ($22), see rockauto. Rear 10" drums were rare, but now are cheap too. 10" drums are better than 9", both better stopping reserve and the hub bearings are bigger.

There were no 5x4.5" drums for A-body cars. I don't know anyone who has installed drum brakes from B,E, or C body cars. Why do so since disks are better. You want your spare wheel to fit either front or rear.