OMG! Have it pinned in place, then welded by a competent welder. The pins will help keep the piece in place. It will be stronger than it ever was before and if someone does the repair that REALLY knows what they're doing, you can simply run a tap through the hole, clean up the threads and go.
My GAWD. You'd think nobody on here knows a FRIKKIN thing about how to weld cast iron. Stop wastin your time here, where nobody knows a FUKKIN thing and take it to a good welding shop.
