Dust, pitting, oxide how this can affect?

Hi i have the oportunity to buy a 7 piece mapex saturn IV including hardware for 1400.00 dlls, the only prblem is that the rings and the lugs have dust and a little pit and in one hoop a little of oxide, the hardware has a lot of dust altos all the chrome in the drums and the hardware are like they were dirty, i tried to remove the dust with my hands and it seems it's possible to remove but the oxide and pitting maybe not, the shells interior are with no problem, the screws don't have any oxide or moisture, the finish is in good condition only with dust
Do you think the price it's ok? Do you think i could have a durable kit with this conditions? The kit has been placed in a smoky and moisture enviroment
I would like to know your opinions Thanks

Dust, pitting, oxide how this can affect?