Has he tried Home Depot? I notice that a lot of their employees appear to be retirement age and older. The very nice man who helped me with cabinets at the weekend was an ex-VP of IT at JP Morgan, so I don't think you need to have a trade.
I was at home expo in Commack..they have a lot of older help there. The man who helped us was a retired school teacher and now works as a salesman in the bathroom cabinetry area. It's worth a shot...I wish you and your family good wishes and job dust for your dad.
I hope he finds something soon. It's unfortunate that so much age discrimination goes on and it's nearly impossible to prove, so it's hard to do anything about it.