Defender 110 hi cap drivers door window

Ok. I slammed the door on mollie and the window shattered.
Replacement glass appears to be over 100 quid.
That's ok if I have glass insurance. At the moment I've taped 2mm polycarbonate sheet on the door.
I can get 5mm polycarbonate sheet big enough for about 35 quid. Would it be legal to use this for the drivers door window?

Forget that. Just found out it has to be kite marked toughened glass.

and a window glass is around £100 and I don't have glass cover so.....
the doors are RTF (rusted to ....) dented, scratched an generally buggert.
The hinges are worn out, the catches and striker are also buggert. The driver's door doesn't lock unlock on the key and the door cards are in pieces.
replacement doors - 2 piece - primed, with sliding windows, new locks, latches, strikers and hinges, series type recessed handles, £428 the pair. Delivery Monday