Stitching the block is a permanent repair, better than any epoxy. You can read about it here:
http://www.locknstitch.com/engines-casting-repair-industry.html
I have no affiliation, but I can say that a V-grind will not allow a proper repair later. Anyone who can operate a drill and a tap and die can make a permanent repair in a few hours time. Basically the kit drills, taps, and plugs with cast iron along the crack, then you do a second round of the same that overlaps the first. This locks the "wedge screws" from the kit in place and seals the crack permanently using cast iron, not glue. General cost - $200-300 but that gives you the tools and enough materials to make a lot of repairs.