This torch is by far the best to use for repair welding on most
metals but is great for cast iron:  http://www.cobratorches.com/

You may be able to contact them for some leads to restorers of car and
airplane motors or steam/early engines.  They all use the torch for
cast iron repair.  I have used it on small cast iron items.  I do not
have a oven for preheat but have used a large bore propane torch (the
weed-burning type) or a charcoal briquette fire and, after welding,
heated sand for cooling.  Small items don't take as long to cool.
If you are near a larger city you should be able to find somebody to
repair it.

This style torch is also used a lot by blacksmiths for horseshoe
work as it does aluminum welding with only the acetylene and oxygen
bottled gas, so the cleats and traction devices can be put on the
aluminum horseshoes on the site.

The usual disclaimer applies.  The only connection I have to the
company is being a satisfied owner and user.

Glen R. Perye Jr.

 [ I had better luck connecting with  http://www.cobratorches.us/
 [ and http://www.cut-like-plasma.com/  -- Robbie