Need thoughts on rusted Spindles/Knuckles

Rear knuckle/spindle thingies.
I can't tell if this is some undercoating that's been trashed, or if it is the original finish that has been totally eaten away by rust. This is how they looked before.


After an hour in the hand sandblaster:



And, these are what the original finish looks like, with light surface rust & dirt:
(this is my replacement part if I can't reuse the old stuff)



Imgur Album for Full-Res pictures.


I would prefer to use the original part I'm blasting when I can afford new bushings (planning to continue blasting, prime & paint).

For the time being, I am going to be putting the parts I've pulled (pictured last) on the car.


New replacements are $230 a piece. Think mine are in good enough condition to keep and continue spending time on blasting? Or is there too much pitting / compromised?

Any tips/ideas? Thanks.