You can even try ebay for some stuff. There is a run dry impeller available, for example [not that this is the recommended procedure]. I don't believe Yanmar makes belts, so if you have the specs, you can use any manufacturer [just cross referencing part numbers does not always produce accurate results]. Lots of folks have modified the air intake to do away with the OEM filter which fairly quickly seems to end up as a crankcase oil dye.