Fire and water damaged guns can often be brought back to working condition.  Unfortunately, I have had considerable experience with these, and wrote an article published in the March 2006 "Amercan Gunsmith" detailing ways to work with these guns.  If your gun(s) have suffered water/fire damage, here's what you can do:  Safety First-make sure the gun is unloaded.  If it's rusted shut, use a cleaning rod and measure the distance from the muzzle to the breach inside and out.  If the inside length is noticably shorter, then you may have a round in the chamber.  Place the gun muzzle up and pour in some penetrating oil-Liquid Wrench, Kroil, WD 40, diesel fuel or kerosene.  Wait three or four weeks before you try to open the breech.  If there is not a round in the chamber,  remove the stock and soak the metal in diesel fuel or kerosene .  We want to seal the metal against oxygen.  Grease is not so good, some are water based or acidic and it's easy to leave an air pocket when you're applying it.  If you can put the stock in a dry and warm (not more than 110 degrees) environment, that will help to slowly dry out the wood.  Nickel plated guns should get the same treatment. 
Give me a call or email me.  I have restored some pretty horrible guns, and I might be able to do yours.  Ship me the gun, I will evaluate it and let you know what I think can be done and how much it will cost.  If its too much, I'll ship the gun back.  Your only cost will be actual return shipping.  My turnaround time for water/fire damaged guns is slow, sometimes as much as six to nine months.

Water damaged Winchester  70
Here's the bolt from the same gun.  All but the scope were saved and restored.
A little friendly persuasion with a two pound hammer, an impact tool and Kroil will often loosen rusty parts..
The bore on this gun was bright and shiny because it had been heavily oiled before storage.    The outside pitting was too deep to high polish, so we did a matte bead blasted finish and the gun is back in service.