Any of the Samson Top Mounted Deployable Front and Rear Sights that are designed for: Gun Model - AR15, will provide a lower 1/3 co-witness when paired with the Eotech EXPS-3.
The Samson Folding Sights Package w/ Front Sight and Rear Sight models QF-HK-A2 PKG and QF-A2-A2 PKG will work for that rifle and sight.
Any of the Samson Folding Sights Package w/ Front Sight and Rear Sights that do not use an extended front and are designed for the AR15 (MPN:QF-HK-A2 PKG and MPN:QF-A2-A2 PKG) will be a perfect co-witness with your HS512C red dot sight.
The Samson Folding Sights Package model QF-HK-A2 PKG should co-witness with an EOTech on an AR15.
The AR-332 and 536 dots are 1.6" above the rail. You would need the extended height.
Yes you can, your sight radius would be pretty short, but it would work.
Yes, these would work on your Tread.
It would fit the model with the full-length rail. Otherwise, on the models that just have the rail on receiver, that would be way too short of a sight radius.