Marx Racer

Q: I have wanted to own this windup tin toy car for a long time. Recently my old friend decided to part with it. It was a Christmas present given to him when he was a child. The front license tag says “50-50” and it’s marked “Mar” on the trunk. It winds up and works nicely. I want to add it to my collection of other toys and want a fair value for insurance coverage. Can you tell me who made it and what it’s worth?