Have the oppurtunity to buy a Crestliner 19' 1970 Norseman Runabout aluminum boat with a original 120 hp omc inboard.....boat is all original and in nice shape....my concerns are the omc inboard how well are these engines??? I"am really concerned about parts being available for it at 42 yrs old engine...would greatly appreciate any and all info and opinions on this boat (Engine)....it's definitely a great looking boat! Thanks for any help.. .