You should be able to buy the glass from any windscreen firm, not sure if the trade surpliers will sell to the public. Not sure about shipping, could you pack it yourself to send.
I had the same thing after I replaced the expansion tank. It only stopped after slowly undoing the cap every time the gauge went into the red, only enough to get the coolant to fill the tank. I guess it had a air lock somewhere.
The axle nut was not a problem after i knocked the stake nut out of the groove in the axle. I am blessed with a body designed for jumping on the end of a long breaker bar.
the hardest part was removing the hub after I had unbolted it. I managed to loosen it by knocking it around until one bolt...