If Timken or BCA/National #5756 is what you need, check Rockauot.com. Their prices are about $8 and $12, respectively.

TIMKEN Part # 5756
Category: Wheel Seal
$8.31

BCA/NATIONAL Part # 5756
{Oil Seal / Felt / Shaft Size=2.062" Housing Bore=3.151" Outer Diameter=3.156" Width=0.24"}
Category: Wheel Seal
$12.24