KB label is
1951 data (Glass-study.com) -
KOSCHERAK BROS., INC., 129 Fifth AveÂnue (3), GR 7-7733. F. E. Koscherak, president; Morris Blau, sales manÂager.
Imports from England, Italy, France and Germany in china, glass, pottery.
category: Fancies - represented in Chicago by: W. C. Owens, Inc., 1520 Merchandise Mart.
Current web data -
Koscherak Brothers Inc - Giftwares (Wholesale)
448 W 16th St, New York, New York 10011
(212) 627-2050
If they still exist a phone call may answer the puzzle.
This pottery mark proves that KB was NY
http://www.collectorscircle.com/bohemian/Porcelain-2/porcelain/marks/gs004Koscherak-Mark-1.jpgA Jack Badash of Javit glass fame was employed as a shipping clerk at KB in 1936 before starting his glassworks. Pushing date back further in time.
It is likely related also to Austrian Bohemia Koscherack Bottling Works that existed up to around 1925 and then reappear as Koscherak Siphon Bottle Works, Hoboken, New Jersey importing soda siphons from Austria.... dating coincidences maybe but a strong suggestion that this was at least a family connection. So KB NY probably came into existence in the 1925-36 period perhaps taking advantage of the depression?