Someone who is very talented with a torch can braze the piece back on, but something that small is basically cosmetic. I'd still choose to incorporate a brazed-in stud as part of the repair. Actually welding cast iron involves nickel-alloy welding rod, pre-heating the casting, peening for stress relief, and post-heating with a very slow cool-down buried in sand. It's a specialist's job. If you use a block-mounted starter, you'll have to cut away the area of the bellhousing where the 3-bolt nose of the older starter mounts to the bellhousing. I have one modified like that on my engine dyno setup.
Jerry
Last edited by Hotrod Lincoln; 02/08/2011 11:57 AM.