Hi John,
There's a 4K version of the RunCam Scope Cam too. [Edit:] In 4K mode, it only runs at 30 fps compared to 60 fps in 1080 mode[Edit End], but I think more detail will probably be more important than a greater frame rate.
I'm not sure it will be possible to aim a camera with a tele lens reliably with a head-mounted setup. An alternative option might be to mount the camera to the binoculars instead ... not quite as "always on", but I imagine this will result in better image quality.
Here is an example of such a mount:
NATO/Picatinny Rail for Binoculars (Parametric) Mount NATO/Picatinny/Weaver compatible stuff on your binoculars (i. e. action cameras). Works with binoculars that have a 1/4" thread in the hinge.
www.thingiverse.com
(Obviously, it requires binoculars with a tripod adapter screw in the bridge.)
Regards,
Henning