Need orfice for nat gas drill size 29/or5fice size .14 where to get parts

Many GOOD hardware stores carry them. Try ACE, not HD or Lowe's. You may be able to get one at an HVAC supplier. Many have the same thread size but you should start with a brand specific supplier as a Goodman orifice may not fit a Carrier etc. If you have the proper fitting orifice, buy a #29 drill bit and do it yourself, brass is easy to drill.

I believe that is a moblie home furnace. You are likely going to have to go to a dealer of Nordyne (Miller or Intertherm) furnaces to get that orifice. If you are converting from LP to Natural gas, you also have to convert the gas valve. You can drill out the presumably existing LP orifice to the #29 but it's best done in a drill press where you can make sure the drill bit is exactly straight.