How long are you gone for? If it's just a night you can probably get away without pumping but I'd have thought much longer you'd want to pump both for supply and your comfort. Does he usually take milk in a bottle or sippy at any point in the day? If so I'd just do that
but if not I probably wouldn't introduce a bottle at this age, you could leave some milk and they could try a sippy but he may not be keen. To be honest it's probably not a major thing if he doesn't take any while you are gone though given his age, he can get plenty of calories from other sources for the period you are away and you shouldn't need to wean unless you want to x