Ouch!! [emoji33]
I paid 360 from toyota for my rear screen, you should change the gasket too
I just priced up a new rear window from them but then noticed that they don't supply glass for international shipping, probably due to the risk of damage? I then got 2 prices from well known glass suppliers over here and the cheapest came out at £245 fitted so was a lot cheaper than it would have been from Amayama anyway. The price from the 2nd glass Co. was £200 more!!
I would be tempted to try cleaning the breaks in the element and bridging with solder. Cracks can be found with a multimeter. If it fails then it's £245 fitted.