Just a quick FYI:

I needed a rebuild kit for my Zenith K5A.
I found a guy that remanufactures Antique carbs.
He charges plenty but will put them back to factory specs.
He makes the rebuild kits himself.
He is very knowledgable and friendly.
Has been doing this for 30+ years, & has thousands of kits.
He wanted $65.00 for a K5A kit.
A quick link into his web site is:

http://www.thecarburetorshop.com/Tractorkits.htm

I then called Zenith!
They stopped making the kit, but due to new demand have now started again.
They said the kit was $33.00 but would not sell to an end user.
The gave me the number of their largest Distributor,they are located in Ohio.
I called them and they wanted $28.00 + shipping.
Came out to $33.00 !!
Got it in 3 days and I am happy!

Contacting Zenith
14570 Industrial Park Road
Bristol, VA 24202
(540) 669-5555
I think the girls name was Beth, not sure.