544 Utility Carb question

I cease to be amazed anymore with things I see coming into the salvage yard. My guess would be that someone found a carb from some other application which would fit. As for the three carbs which the book calls for I will list them and give you my opinion(such as it is)on each.
The three carbs are a marvel-schebler Part#398069r92---Zenith part#405030r91---I.H. part#406804r91. I would first use the I.H. carb. It is built well and you can still get most of the internal parts for it. Secondly go to the zenith. The biggest drawback is they are made out of pot metal and most I get in to be rebuilt have the threads stripped out. Otherwise it to is fairly common and easy to get parts for. I would not, however use the Marvel-schebler carb. While they are the heaviest built of the three carbs, I have found you cannot find the parts to rebuild them. Especially the jet which goes into the fuel shutoff.

All three carbs have the option of a fuel shutoff but you do not have to use them. I actually have had to put together main adjusting needle/packing/packing nut kits for many guys who use these to help adjust the fuel mix in the I.H. carbs. The Zenith carbs you can also put an adjusting needle in but I have heard they are not as useful but do serve to remove the fuel shutoff.