All of the aftermarket or even OEM boys require a business number to have an open account. Now you can buy all the parts you want at retail using a credit carb, but as far as ordering direct, not going to happen with a business.
Out of the three Bert listed Stens is the only one that distributes direct. Oregon and Rotary work through other companies that also distribute Briggs, Kohler, MTD etc. So for example. A briggs distributor will not sell Oregon parts that replace briggs. Kohler distributor will not carry oregon parts for Kohler.
