1998 Volvo V70 Question: Do I need timing belt replaced at 33,300 miles on always garaged sdtation wagon?

To be direct- NO. It does not need to be replaced. Not at that mileage. Sounds like another case of a dealer taking advantage of Senior Citizen.

Even if the replacement interval is 70,000 miles, unfortunately rubber components will age and crack even if they are not being "used".
They are easy to inspect, the coolant reservoir has to be relocated from the way and the timing cover removed. A good technician will be able to tell you the condition of the belt and advise you about it.

Zee

BTW: this is an interference engine, so engine damage will occurs in case of timing belt failure!

My opinion is "if it ain't broke don't fix it." Save your money..I have a 1997 car and still haven't had to replace mine.
If they can show you visible signs or wear that would be another story, but even if they can, if you may not be able to drive it for a year or so I absolutely wouldn't put a dime into the vehicle.
I hope you take my advice. My dad is your age and I'd tell him the same thing, if that helps..