if you post pics here it can normally be IDed...
If you don't have any pics on your PC( if you do we can help you post them)
www.boattraderonline.com has alot of boats on it. if you are sure its a 75( or just 73+) then it should have a HIN( hull ID #) there is a USCG site that has listings of all of the manufactors.. http://www.uscgboating.org/recalls/mic_database.htm