I have never seen one of these Kastoo. I have seen fruit jars on eBay bring some pretty good money in the cornflower blue color. I would say your jar is most likely a pretty good one as for its name. I have never found one of them in my area, I like it!
i dont know much about jars im not really the "jar guy" im more into soda's but my dad likes the fruit jars so i have seen alot of them from that i have picked up quite alot about which ones you see alot of and what they sell for...that being said i like that bamberger and have yet to have seen one...nice jar! also cornflower or aqua of any shade is a common color for fruit jars