Hey rgsuperstrat, thanks for the pictures.
The Price Guides are not much help with most Kay guitars. I like what Zach wrote under the Kay Pro entry in the Blue Book, "The secondary market is still undefined".
I think we need to turn to eBay to help establish value. While there is no guitar exactly like yours up for auction at the moment, there are several Kay thinline models up that should assist with establishing value.
Here is a value leader thinline that the guy wants a minimum of $425 for. You may want to watch and see if he gets it:
http://cgi.ebay.com/60s-KAY-Value-Leade ... rms=66%3A2
Here's another value leader that needs to be cleaned up but looks to be original condition:
http://cgi.ebay.com/VINTAGE-KAY-HOLLOW- ... rms=66%3A2
I'd say your thinline is worth a bit more than these later examples due to the speed bump pickups. Good luck.