I could be wrong, but your old paraffin should be rock solid stable for years. It isn't volatile at room temps and fairly inert at room temp as well. You didn't mention if it's liquid paraffin oil or solid paraffin wax, but both SHOULD still be good. This quote is from wikipedia:

"The name is derived from the Latin parum (= barely) + affinis with the meaning here of "lacking affinity", or "lacking reactivity". This is because alkanes, being non-polar and lacking in functional groups, are very unreactive."

Don