SOOOOO much depends upon your local market and demand. Where I live, old Kays are the Blueridge Cadillac and in huge demand. Austin also has a very strong interest in everything musical and Americana. About once a year, I drive out to the midwest and literally fill up my pickup truck with a half dozen old Kays for around $2k.
$2500 for that cosmetic condition and year would be close to top dollar if you bought it from a respected shop. Buy from a reputable shop and you generally know that if you have any issues, you can bring it back and they will stand by it. Spend that much from someone on craigslist and you had better know what you are getting into and accept it. Remember that old beat up Kays are as common as old beat up Volkswagons. They made 30,000 of them, so there should never be any pressure to buy one immediately.
Here is a good reference point for valuing your old Kay bass: http://kaybassrepair.com/what-is-my-old-kay-bass-worth/
Be very cautious about the craigslist / ebay mindset of, " Jerry Garcia had a red one and it sold for $25,000 and mine is red, so I want $25,000....."
If you have an ipad or iphone and a facetime or skype account, you can call me at the shop and we can go over it together with a live video stream. No guarantees without having it in person on my workbench, but a second set of eyes kicking the tires help a lot.
j. www.kaybassrepair.com www.condino.com