I've got 8x Yakima A1 towers (for roof racks, attach to standard econoline roof gutters) that I no longer need. I have 1 set (4x) that have matching lock cores (and I have at least 1, likely 2-3 keys). The second set of 4x has lock cores, but only 3x have matching lock cores and I don't have keys for them. I cannot confirm that they second set's lock cores function because I don't have the keys to test them, but I'd presume that they do work. Photos show lock core key #s.
These are currently selling for $200/set without the lock cores. Asking $100 for the matching set and $75 for the non-matching set. Located in Seattle, I can ship at buyer's expense.