My Old Spalding mallet head putter

I've had this putter since the 1970s, yet I know nothing about it. The lettering, which is partially covered up by lead, says "Spalding Long Green," (I think). The three dark areas on the head's bottom are lead. It has an original curved leather grip with a diamond pattern. It measures 35 inches. The hosel ferrule is reddish brown with dark swirls. Any information on this old-timer would be much appreciated.