I have not purchased from 1sttoyotaparts. You could go to your local dealer and see if they can get the part number. Sometimes 1sttoyotaparts shows parts being available that are no longer available.
Here's an old post from someone who has ordered from them: IH8MUD.com Forum - View Single...
Here's a thread with some discussion about how to wire it. Post 2 of that thread has a link to another thread/post from me with my original write up.
https://forum.ih8mud.com/60-series-wagons/130865-inclinometer-wiring-60-a.html
If you can get the knobs, it could be a good find. I got a chance to try out the Toyota Parts EPC I got from someone else here. The knobs are shown as position 83891 and this is Toyota Part number 83891-16010. When I look up this part on 1sttoyotaparts.com, it shows as being available and...