I'm thinking this washer is from 1976 to 1978/9. Although the control panel and agitator were around for quite awhile after, the lint filter looks like an older style than those that I have seen on Whirlpools and Kenmores from the 1980s. I don't know if this is the bed of nails type filter, but judging from the outward appearance, I am guessing this particular filter was issued in mid 70s Kenmores.
Have a good one,
James