As long as the brass is just discolored and doesn't have any grime or crud, I would say load it up for target grade ammo. I would advocate being conservative in charge weight. You don't know what brand or type of primers are in there. I standardized on magnum primers for pistols since that was all I could get for a while, he might have done likewise.
If depriming and cleaning is the route you want to take, my vote would be a Lee decap die, safety glasses, and save the primers for target grade ammo.