Old grills such as this that need work and parts should be available for about $40 or less, and the things they, the cheaper they should be.
A grill such as yours, you would likely want to give about $25 or less for. So use that as a guide. If the lid is in nice shape, $25 would not
be out of line at all. If you REALLY REALLY want that green lid, then the skies the limit.