Hi Ernest,
What do you want to use the trimmer engine for? If you need a clutch, it must be for a bike, RC car or boat, right? New trimmer heads are routinely found on
www.Ebay.com. Some have clutches and some don't. Toro trimmers have clutches and are very good quality. I have often bought new trimmer heads for $30 USD including shipping. I have seen new weedeater 25cc heads for $25 USD plus shipping. They don't have a clutch. You just have to keep your eyes open. Surface shipping would be cheaper to the P.I. Maybe the australian Ebay would be a good place to look. It is close or the China market which is booming. Don't forget that imports have killer taxes in the PI. Good luck.
Dave