You find commercial models, like the ones made by
OTTO for military use, at "just" $925.00
https://spemco.com/u2-605-water-res...ch-american-made-boot-retaining-feature/And perhaps models made for electric tools(?).
Or look how dual stage trigger are made in comercial joysticks for games - It's just 2 micro switches in tandem.
E.g. In Warthog:
In VKB F-14 grip And DIY one, like this made by Goblin for AJS-37 Viggen grip.
As curiosity, how they are in real P-51 Mustang grip: