I ran across this new Infiray thermal that can be used as a handheld scanner, helmet mounted, rail mounted as a scope, or used as a scope clip-on unit.
This is the sweet spot for me when it comes to thermal lens size and FOV with the 640 core. 25mm with a 17.2 degree FOV. Too early to tell without some feedback from hands on field trials but it looks like they may have hit a home run with this one.