>>..build my own siderostat

Should be straightforward for a small one. The Celestial Pole varies by location (elevation by latitude and azimuth by longitude). The challenge is finding a bearing strong enough to take lateral forces and an appropriate motor (you may need to do counterweighting to reduce the torque required.

If you're in the Northern Hemisphere, aligning an axis with the North Celestial Pole can be done with a guide laser. The NCP is about one degree (two times the apparent diameter of the moon) away from Polaris on a line to Kochab. (I do it this way with a camera w little tracker; no smearing at 10 minutes). [NOTE I got the degrees wrong on an earlier version of this, editing so I don’t screw a budding night-sky photographer up. It’s really 3792 arc-seconds which is pretty close to one degree — IMO close enough if you’re using the mark-1 eyeball.]

Instead of all that, what about a Foucault's Pendulum with a seat :-)

I've gotta admit: I have never had the urge to climb onto a tracker.