Ultegra / XT chain available (with one Shimano Quick Link) for $45 at one of my LBS:
Shimano XT HG701 11-Speed Chain - Southern California Bike Shop | Jax Bicycle (jaxbicycles.com)
When I bought a spare early this summer it was still only $40, which was already $5 more than the one currently installed on my bike.
Shipping is a bit expensive but what isn't nowadays?
Maybe
jnbrown can order one for pickup at the San Clemente location if on the way to do something in the OC?