B carb has sprung a leak

Howdy.  After I drove my 1940 B around the local show last weekend, it became apparent that my carb had sprung a leak on the bottom.  It was a pretty serious drip that I was able to stop by shutting off the gas flow at the sediment bowl.  I suspect maybe a sticking float or deteriorated gasket or o ring or some such thing.  Is a carb rebuild in order here?   It is a Zenith carb.  How do I determine what kind/ model number I've got, so I can find a correct rebuild kit.  Would Stieners be the best route for a kit?  Any help would be greatly appreciated. 

you could start by banging on the side of the carb with a small hammer, bar to see if that will POP the float off the STUCK position.. Sometimes that happens and not a big deal.. If you want to rebuild it, youi normally get a gasket and possible the needle shut off in the KIT.. Normally you dont get the FLOAT or jets unless you pay extra.. Look at the sides of the carb.. Sometimes there is a round disk about the size of a nickle with a rivet in the center... will have the model number on it... Normally there is only 1-2 different ZENITH carbs used on the B-C tractor and they will all use the same KIT..