Still encouraging you to rinse the pistol out as described in my post here ... to prevent further corrosion and damage. This is not something you should be waiting around to do. The longer you wait, the worse the damage will be. If you can't do anything about it now, at least rinse the gun in water, shake/pat dry and then leave it submerged in a bucket of motor oil and ATF until you have time to do it right...
Salt water in and of itself isn't really THAT bad for metal in the short term. The short-term damage comes from exposure to salt and moisture (in your case, salt water, salt water spray, etc) and THEN air. This is why you see black boxes recovered from oceanic air disasters being shipped in coolers back to the lab for analysis. There's water in there ... likely fresh water (perhaps distilled) but water nonetheless. The lab will execute the proper procedures to flush the equipment out under controlled circumstances prior to attempting to recover any data. Their procedures likely involve copious amounts of lab-grade distilled water followed by compressed air and/or alcohol and/or small amounts of heat. These procedures are for recovery of electronics.. the instructions I provided in my earlier post are for handguns... but the net effect is the same: Get the salt and moisture away from the item ASAP by rinsing, minimizing it's exposure to air, and in the case of a pistol, apply a protective coating.
I'd venture to guess any refinishing job involving sending the pistol out (be it to S&W or a custom shop) will cost about $100 just for shipping in both directions. You're probably looking at $250-$300 or so when it's all said and done.
You might want to pose this question on the Gunsmithing & Repairs sub-forum.
