I have a 115 carb with model J mixer. It's been sitting around for a couple years, so probably needs gaskets. I'll toss in a $100 bill on the trade. Here's the specs on my stuff. Do you have a vacuum lcok off? If not I can do an even trade and I will buy a new lockoff.
Impco 55 Series Carburetors & Mixers - Positive & Negative Pressure
Standard Carburetor for CNG & LPG Fuels
The Standard model can be mounted in an updraft, downdraft, or side draft orientation, supplying wither LPG or natural gas to engines from 1 to 52 kW (1.5 to 70 hp). The maximum flow rate is 54.2 L/s (115 cfm). Various SAE flanges and air horn sizes are available.
Model J Series Two-Stage Converter for 3.7 to 75 kW
for LP-Gas Engines
The IMPCO Model J Series converters deliver superior performance and excellent pressure output consistency throughout service life. Three vapor outlet pressures are available. Use of the standard blue secondary spring provides negative 0.37 kPa (-1.5 inches w.c.). The optional orange secondary spring provides negative 0.12 kPa (-0.5 inch w.c.) and the red secondary spring negative 0.05 kPa (-0.2 inch w.c.) output.
Impco VFF30 Vacuum Fuelock Filter
The IMPCO VFF30 is a combination fuel lockoff and filter engineered for use with LPG or natural gas. A pressure of 1.69 kPa (0.5†Hg) is required to open the lockoff. The VFF30 is suitable for engines up to 242 kW (325 hp) at a maximum working pressure of 2,150 kPa (312 psi). The filter element is fully serviceable.