How old is my Mickey Mouse toy? Can anyone help please

Hi, I have a Rubber Mickey Mouse toy which was handed down and was my favourite toy as a kid. I don't know where he came from or how old he actually is so thought I would post this to see if anyone recognises him. He is 8 inches tall. Well loved as you can see with red painted on shirt, yellow pants and is showing his teeth. On the back you can just make out Walt and Prod. Also on the back there is a triangle symbol and the word "playmate". Any help would be greatly appreciated.