if the scratches are deep enough to catch your fingernail on then resleeve, if not then you can hone and rering it but dont expect compression like new.
after you factor in the time, parts, and downtime on fishing its usually a wash between buying a new powerhead vs rebuilding it yourself.
if you have lots of spare time and would really enjoy doing it yourself even if it turns out badly then it can be a fun project but in most cases it makes more sense to just get a new powerhead because once you get into it you have broken bolts and stripped threads or unseen damage you find
Man, I had the same model on a 16' Lowe aluminum boat. That was a great motor!!! (but awful on gas!!!!!!). I ran it many miles in the mud, hit rocks with the lower unit and had that boat 20 miles offshore, but thats when I was young and stupid. Wish I could help you with you're re-build, I just buy a new one when they wear out.
Good Luck!!!!!