polishing pins of NOS tubes

I've used a Dremel many times to clean up tube pins, it's not difficult at all as long as you pay attention to the direction of tool rotation and use it correctly. I use Maas metal polish on a small felt wheel as opposed to the brass brush though. Even if a pin gets bent a little, a quick tweak with a pair of needle nose pliers gets them back in order. Then clean the residue off with alcohol like the previous post describes. I also have used the exact same procedure described above with the exception of using very fine grit  wet or dry sandpaper strips cut 1/4" wide instead of a polishing cloth. Usually 1000 grit works fine. 

Don't worry about it, use the steel brush on the steel pins. If you come across copper or brass pins, use the corresponding brush. After brushing, wipe off the pins with an alcohol swab.

I've used Deoxit with great results.

I’d try Deoxit first. I think a Dremel variable speed cordless with the small felt wheels would be good . Personally I’d anchor the tube in a safe manner on a flat surface and use both hands resting on the same surface to avoid a woops . I’m fairly experienced with accuracy rifles and avoid using stainless brushes on stainless or regular steel barrels. I use a high quality brass brush. We have different solvents to use mainly to remove copper buildup and we need to be careful not to etch the barrel. Those solvents usually have a strong ammonia smell. I’ve often used a fine paste valve lapping compound for various metal related tasks like lapping aluminum and steel scope rings. A polish like that might help.  I’m getting off track for your sake but just wanted to share a general overview of stuff as not to get too carried away. I hope my abstract speech helps in your search. Regards, Mike B.