There are three LOC-approved vendors that can clean your boat and attach the required LOC tag:
West One Marine
221 Foothills Road, Lake Oswego
503-702-0450
River City Boat Sales & Marine Services
26177 Boones Ferry Landing, Aurora
503-797-2222
NW Boat Sports
18649 S Hwy 99 E, Oregon City
503-305-5168