I have a red riding mower lawn tractor there is no name only the numbers 12-39 on the side I believe this to mean 12 horse 39' cut who makes this the model? Model number is C3912110 code 2050 noma .

A little internet research: Noma was purchased by Murray and now in the hands of Briggs and Stratton. Support is supposedly very limited. Anything made prior to 2002-2003 is not supported, so I guess you'll have to rely on aftermarket parts.