Hi Mrs. B,
Your guitar was produced in 1955-56 and appears in the 1956 Kay catalog I have in the Electric Guitar Catalogs section of VintAxe. The KAY KANTI-LEVER sticker refers to a lever neck adjustment system housed in the heel of the neck and operated with a skate-key looking wrench.
The most collectible Kays of this period are the Barney Kessel's introduced in 1957, they are bringing up to $2,000 these days
. I would guess your guitar would sell for something between $450-$700 depending on condition and whether you can connect with a motivated buyer. Good luck, sb