This is a problem I share. My windows are glass and bonded in place and like you say if the car turned over a sunroof wouldn't help in getting out. ...
There's a couple of good facebook pages - one is called Purvis Eureka Car club of Australia which is very active and which caters for the Australian...
I don't have them on mine either and whilst I never had my car MOT'd it was checked over by an MOT inspector who declared the car fit and never said...