Ford called this body style "Flareside". Ch**vy called it stepside.
This question has been posted mutiple times before. Usually folks are hesitant to give a dollar figure. Worth will vary from person to person. Usually someone will put out a high figure and then others will jump in and say why it is not worth that amount to them.
So...., if you want to go down that road, post up some more revealing pics and give out with the details as to condition and originality etc... If you want, I'll throw out a figure of $1500 and you can tell me why it is worth anymore than that! LOL!