47-55.1 Axle Seal / Wheel Bearings

[Darthintel]

I bought a 1954 Chev 3100 truck and started working on the rear brakes.
After removal of the drums I could see that it had leaking axle seals.
I ordered all new brake hardware (brake shoes, springs, wheel cylinders, master cylinder, rear axle bearings and grease seals).

I removed the brake hardware and pulled the axle. I then pulled the oil seal and compared to the new one...something is wrong. The bearings and axle seals I bought are too small.
I'm thinking I have a 1 ton axle under my truck based on the fact that I can count 10 leaf springs.

I took the following measurements:
Axle tube opening:
70.33mm / 2.76"

Old oil seal:
70.39mm / 2.77"

New oil seal:
61.3mm / 2.41"
Part number National 450666

New bearing:
61.25mm / 2.4mm
Part number National R1500EL

Since the parts I ordered for a 1/2 ton truck are too small, I'm thinking I have a heavier duty axle under the truck but need help identifying.
The 10 leafs in the springs are a clue. Is this a 1 ton axle?
It does have the enclosed drive line.

Thanks in advance for help.