Well, there's certainly some value, but I'm not the guy to give you an appraisal.
I do know that some folks really like the Service/Speed/Security-Six series. It would seem to me that a fixed-sight snubby would be a commodity that would have a market.
I would call Ruger, and verify that the gun is stainless, which would be my bet. Since the gun was available in stainless, the odds of someone nickel plating it should be fairly low.
I'm sure someone will be along shortly to give you a better idea on value.