[Marshall V. Daut]

It is not necessary to buy a "new" Zenith, nor especially bullet-proof. I have friends who have bought "new" Zeniths and their quality and performance are all over the map. I have had to go through three of them and correct problems. Others say they have had no problems with theirs. Too risky in my opinion and not necessary because there are so many original Zeniths out there to be had. A number of guys on this website rebuild them for less than the vendors charge for a new one, or you could buy a rebuilt one from Bert's Model A Center in Colorado. The quality of Steve's rebuilds is legendary. No risk, no problems. Quality.
But try to fix your carburetor first, not only to save a ton of money, but also for the satisfaction that you personally made a successful repair. You will also have learned a good deal more about repairing your Model A. That's a confidence booster for sure!
Marshall