Marlin Model 100

So I'm talking to a coworker today and the topic of pawn shops and guns comes up. She says - "Do you have any interest in an old .22 I have. It was my ex husband's, and it's just been sitting in my closet." I told her I would love to at least take a look at it. It's a Marlin Model 100. Judging by the fact that it has a micro-groove barrel (which Marlin started in 1954) and the model was discontinued in 1959, I'm assuming it was made sometime in between. No serial number that I can find. There's a fair amount of rust on the outside, and it's hard to see but I think the bore may be a little rusty, too. The stock seems to be in pretty good shape. Does anyone have any good information on this model? I've looked for a while on the net, but found very little useful information. I'm thinking I'll offer her $50 for it.

Forgot to mention the barrel is stamped as follows....

The Marlin Firearms Co. NEW HAVEN CONN. U.S.A. - EST 1870
Model 100 - 22 CAL. - S - L - LR -----*----- A
---- MICRO-GROOVE ----

I've looked through several of my books and can't find any more info. I did read that in 1956 they changed to a walnut stock. Prior to that they were birch.

Thanks. Can you tell from the picture which wood this one is? I don't know squat about wood.

Not really. They used a walnut stain on them to make them look like walnut. You may be able to tell for looking under the buttplate. Birch is a really light colored wood.