Tbh with your age and distance, it just simply doesn't seem like it'll work out... BUT...
SNAIL MAIL! :D
Send him letters, back and forth! When my best friend moved when I was younger, she and I sent each other letters every other week, and we always sent little presents, like handmade bracelets or cool rocks :) And there's no better feeling than to come home and find a letter from someone you care about very much in the mailbox!! :D
We also called each other once a month on our house phones! But, I'm not sure if people have house phones anymore, my friends always think I'm 'old' or crazy for having one... In that case, just borrow a parent's phone!
I hoped this helped, even a bit :)
BEST OF LUCK!! <3