Nick, try tapping the pulley in and then with two screw drivers try to move ir out (off ) just little also spray with nut buster or any penetrant
U may have to move it back and forth a few times before it comes off,,, about 10 years ago i had one stick, so bad i had to use nitrogen
to freeze the shaft and i small torch to heat the bearing, after i got it off i sanded the shaft , i think i took off .00001 thousand ,anyway
from then on i used anti seize on the shaft. jim