Shaun,
Your engine looks more like an Echo then the Mac's that we have in the USA. The europeans have Mac's based on Poulan/Weedeater engines. I did a conversion on a Echo basied US Mac. Yours looks like a great canidate for conversion. The flywheel is the same as the one used on the 25cc Toro. You can get some idea's on how to convert it and nice mod's from the "Who's converting Toro trimmers" forum. The old "Don't forget Echo" forum is also useful. Just do a search of the conversion forum. You will need a bigger carb of something like 11mm to 12mm and a free breathing muffler. Either gut the stock one or buy or make a new one. A resister spark plug is a must with mag ignition. Good luck.

Dave