The gun - I'd just take it apart and give it a good cleaning.
The ammo - should be fine but I'd have to look at it to make sure.

Lead can be used in most of E. WA for upland. Some places you hunt do require you to use steel though. Kind of similar to Selective Gear rivers, all the areas are different. If you're in a upland/waterfowl combo area, the only way to be legal is to carry/shoot steel only. Can't mix lead and steel in your vest as far as I know.

Yep, all you need for upland is the small game. For waterfowl you will need the Federal Stamp, and a State Migratory validation...no stamp.

Ike