I am sorting out my deceased father's farm equipment inventory. in preparation for sale.

Among the possible gems is an 8-foot Oliver Grain drill with metal wheels.  It seems to be in very good condition, has always been shedded.  This drill was my grandfather's originally.  The signature greeen paint is still intact, and the seed boxes are spic and span.

Can I get any advice on what the possible age of the drill could be?  Is this a machine with some decent value as a collector item?

As a farm equipment newbie who thought he was out of the farm business when he left for college 35 years ago, any advice on the value of this drill is greatly appreciated.