Hi Mike,
Is this unit you speak of the Harvest Gold skirt model with the white wringer and white porcelain tub? I saw them in the MW catalogue in the 80's I think. If you do find out how to date this I would be interested in knowing also. I have one of the last manufactured SQ's with the shorter legs I want to date. It was NIB and had the original paperwork with it dated 1991 as the sell date but I would like to know when it was manufactured. Good luck and happy wringing !!!
Jim