You shouldn't really need it. Get a new drive, install windows and take it from there. Just recovered a WP7300 in that manner, and it's documented somewhat in the thread in the test equipment section. Through the service menu it's possible to recal as well, though you want a separate partition for it (I think the defaults are FIRMWARE on C and USERDATA on D).
Basically it's:
Install XP
Install chipset drivers
Install XStream
Install XStream drivers
Install touch screen drivers