I'm with Tiffy. Don't do it. He offered to help, but you initiated the contact, which at some point could be misconstrued (by him).
In my experience, men might say they are okay with harmless flirting, but it's bitten me in the butt a few times, so tread very carefully.
Besides, I would prefer to find my own solutions without being obligated to an ex. There are just too many mixed feelings involved on both sides.