rear axle

[acalex]

Now this might be a bit nerdy, but here goes....

Whilst cleaning and tidying up at the back end of the 1600HF I noticed a well worn alloy plate, with just decipherable stampings:
818.630 and (I think) 018400, the latter presumably the production number

On the front face of the casing, r/h side is the same 818.630, and a longer number, maybe the part number, 2273702

Would these be standard axles on all Fulvias or unique to the HF ??