What's too old for me? Is it just a #?

I recently was hit on by a stranger in the produce dept while shopping. He is 64 I'm 37. We have great conversation, I hesitate going beyond meals together b/c I have a clomplex from the stares we get in public. I look much younger than my age, we look awkward. Im a bit physically attracted to him. Neither of us have kids and a few other things in common. Idk what to do, he is deffinantly wanting sexual relations with me. I Need to get laid but don't want to lead him on. Any suggestions from simular situations?