How old is my Quasar Microwave oven - Model MQ5500?

This microwave has been working and I’m trying to find out how old this item could be. So far it works beautifully and all parts are original.

crwdns2893858:0crwdne2893858:0 crwdns2893862:0crwdne2893862:0

crwdns2894050:0crwdne2894050:0

crwdns2889612:0crwdne2889612:0 0
crwdns2892346:0crwdne2892346:0