i was looking in an army disposals type shop the other day and they had retractable lap belts new made for helicopters. they were only about $20 or $30 each, and i wondered if i could legally fit them to the rear seat of my kombi, as they would be cool and functional to have instead of manually adjusted ones. would these helicopter belts be legal in a car?

If you get an Auto Engineer to sign-off on it, anything is legal!

Do they have any sort of Australian Standard tag on them?

Probally not as the ADR are different to Aircraft specs.