As you requested.
The price is $695 complete kit (just under 25,000 baht I think it will be around 30,000 baht all inclusive).
Just have to make sure that your helmet has the tiny hold for HANS device.
http://www.saferacer.com/hans-device-sport-series-hans-device.html?productid=1296I prefer this one because you can disconnect the helmet
This one you have to take both helmet and HANS off at the same time
This is the CHEAPEST version of this device unless you wan to mount the strap to the bucket seat like me.
This model "Sport Series HANS Device" is
1 pound heavier than the next model up