Maybe one of these similar products would be of interest:-

Rowing Machine Seats Wheel With-Bearing,8x40x10mm Seats Cushion Moving Wheels

Rowing Machine Seats Wheel With Bearing 8x40x10mm Seats Cushion Moving Wheels

Rowing Machine-Seats Wheel With Bearing 8x40x10mm Seats Cushion Moving Wheels

Rowing Machine Seats Wheel With Bearing 8x40x10mm Seats Cushion Moving-Wheels

1X Rowing Machine Seats Wheel With Bearing,8x40x10mm Seats Cushion Moving Wheels