Your serial number falls in the range of 1972-1973.
Ready can't give an informed estimate without pics... condition is everything. Also your location state plays a factor... especially if you're located in one of the unfriendly gun states where prices trend higher.
Do you have any pics? Putting them in a post is super easy.... at the bottom of the editor, click on the little picture frame in the light blue tool bar to insert a pic into your post.