I'm sure, PB will be more than happy to sell a new screen for 302 (for an extraordinary price, of course), so personally I'd carry the device to the nearest trashcan and start nlooking for something new and better, eg.
Pocketbook 622, not available now, but should be in the next month or two.
302 support officially ended a few weeks ago, so it makes no sense to sink further money into it, and the idea of transferring another screen will most probably not work.
I don't know where you are located, but in europe you'll find a fair amount of different readers in Mediamarkt or Virgin Megastores for trial.