Madrid fan here... actually, i think a window may open (a very small one) for Higuain to move during the summer. Right now, Benzema is clearly the #1 choice and he plays all the important games (started all clasicos, atleti, etc.).
I'm an old time Juve fan too. Am french and my teenage years were in the 80s. Huge Platini fan and followed Juve religiously all the way until the scandal. Also Zidane went to Madrid, etc.
In any case, Higuain should be pursued because he is too good to be a second player for Madrid and Juve need a key striker like nobody else.
It won't happen in the winter... but in the summer, if Juve are in CL, there may be a chance.