try Wix on line
Japan
Ashland makes the oil to Kubota spec
Champion Filters (not connected with Champion Spark Plugs)
WIX makes all of NAPA's oil filters
MTD
a person
MTD
AYP
Fram makes them exclusively for O'Reillys. They use Racor filters internally which makes the OEM versions as well.
Cub cadet makes a great line of tractors. You can find your cadet at www.tractorhouse.com
John Deere makes their own lawn tractors(mowers) in Horicon, Wisconsin, USA.
AYP Makes Husqvarna and Craftsman tractors