He is not in California but Dave Clements does this. On his website there is a picture of a beautiful OM converted to 44 special.

I have a 500 Linebaugh built on a Ruger Blackhawk frame that he built. The work is outstanding. The gun is extremely accurate as well.

Heres the address for Dave
http://www.clementscustomguns.com/

Leocal, where are you in Kalifornia? There is a single action smith by the name of Jack Huntington out of Grass Valley that does mostly 5-shot conversions but he might be persuaded to do a 44 Sp conversion. His ph # is 530-268-6877 and his email addy is jackrhuntington@hotmail.com. His web is jackhunt.hypermart.net. Let me know if he will do it as I also have an old 357 kicking around that I've been saving for a 44 Sp conversion.

I'm in the Bay Area near San Jose.

I sent it off to Clements yesterday. He said that it would take about 3 months.