Yanmar is very strict with the protection of authorized dealer's territories. I doubt you will find a discounter. For oil filters you can find an equivalent in Fram. For fuel filters, impellers gasket and other parts find your nearest Yanmar authorized dealer. I have a Diesel Power company as my dealer and although their stock for Yanmar parts mainly consist of maintenance items they can get parts usually in a couple of days. I like they have the exploded views of different components and you can get the specific part numbers that you need. I once needed a part that was in back order and sales rep there mad a few calls and hunted it down for me. They don't do that in Wally World.