I have a pair of K2 Clicker highback bindings that I no longer use.
They were mounted for a little more than a season, but used sparingly. I used to teach, and used a board with these on it so it was easy to get in/out quickly and frequently. Comes with everything you need.
The boots are K2 Sectors, size 12... for the step-in bindings. Used also just when I was teaching, so they have the same "mileage" as the bindings. Great shape, except for a scuff on the right inner heal from skating around and sometimes rubbing the edge of my board.
I was a big fan of this setup. Much better than other(Switch) step-ins that just hold the sides of your boot... while these anchor the heel and toe, plus the ratchet support on the boot itself.
I doubt you are going to get much of a response on this forum. 99.9% of the membership here think step ins suck, myself included. That said, there is a bit of a fan base out there here and there. You might try splitboard.com and graysontrays.com. I know the clickers were big with some of the splitters 2-3 years ago.