Hello annie, Welcome to the forum.
I'm no help as I know nothing about the S&W MRF handguns.
BUT, take a look at gunbroker.com and do a search for it and see what they are going for/asking for.
If you have a couple of good photos I'll be glad to post them for you...photos get much better response.
There is also a Smith & Wesson forum - http://smith-wessonforum.com/forum.php
- where you should be able to get a more informed response.
I want you to get all the money possible that the gun is worth.
Does it look like this?