Road car heated front screens are tiny wires inbetween the layers of glass that are laminated to make your screen.
As it was never an option, my bet would be a one off job only which would cost you more than the car is worth !
The only other thing you could do is do it like the rear window with copper tracks led on the surface about an inch apart, but being so close it'd be like looking out of a jail door sideways I'd imagine ?!
I presume you have no HVAC unit any more so can't clear it that way ?