I have about 10 different sets of Thule and Yakima kayak carriers. All different models for every type of boat and all types of crossbars and T-Slot mount systems.
Examples:
Thule Hull a Port Aero rooftop kayak carriers, J cradle style, one pair
$140 obo for the set, in excellent condition.
Exactly pictured.
I also have Thule 835XT Hull a Port Pro,
$140 for the pair, never used!
Retail is $280 plus tax.
Thule Hullavator $300 or best cash
Several other models also
Yakima Kayak J Cradles or saddles and rollers also.
I was a sports rep and have lots of Thule and Yakima components and accessory carriers. Keep my contacts for future needs.