You've still got three points of location on that pump so if it were me I'd just ride it rather than attempting to weld or braze a bit on that foot....its age related and honest John...
One of my old radial drills (the big Asquith one) has a cracked mount on the forward/reverse transfer box...
It's clearly been like that for years...and I've no intention of introducing unnecessary stresses into it by attempting to close it up...its happy & settled as it is...