I would only ever trust a proper cast iron repair on that, which means a complete re machine of every surface, and not worth it unless it something VERY rare or exotic. Trust me, it has to be rare for it to be worthwhile, I have enquired
http://www.slinden.co.uk/
Although people have welded cast iron, its not a weld that carries much strength, and where there is mechanical stress and heat, i doubt it would survive very long.
these guys welded a massive crack in the head of an engine of my dad's.
