Anyone make pre-cut rear door perspex??

I managed to smash my rear window this weekend, it happened whilst I was nose down a bank, when closing the door it got away from me and the weight of the wheel carrier buckled the door causing the glass to break which left it a bit drafty.

I dont want this all to happen again so I have been looking for persepx rear windows but cant find any anywhere, not precut anyway. I know I can cut my own but my last attempt at cutting perspex used a fair few sheets up before I managed not to crack it and seeing as its a big piece I thought I would look for a precut one, has anyone found one before?

If not whats the best type of perspex to get and whats the best way to cut it??

Cheers

You need to cut it slowly I've found. If the blade gets warm enough to melt it, it'll stick and break the stuff. I've used a jigsaw loads of times, but you need a sharp blade and cut very slowly. I've also used a hand saw, again needs to be sharp with fine teeth..
The other option is to use a router, I've done this too, it's handy for strange shapes. Make a template from hardboard or ply, make allowance for the bearing on the cutter if need be. Again, cutter needs to be sharp, and run the router at a slow speed. You can also put a nice rounded edge on it with the router.
Goes without saying probably, but you need to support the sheet well.

PS. The shavings need to be just that, not blobs of sticky plastic. And get the UV stabilised stuff, it'll stop it going yellow..

If you sandwich it tight between ply/mdf you can cut it with pretty much any thing.
Butter knives and Bananas excluded (just for the pedants )

The plasticshop.co.uk will cut you a piece to any size you want. Not sure on prices though. It is easy to cut yourself though if you want to try it. Jigsaw with a very fine metal blade works well but allow time for blade to cool down in between long cuts or as stated - it will melt itself back together.