There are several vendors who manufacture seats for the 'liners (alphabetical order):
- Corbin - http://www.corbin.com/yamaha/linermenu.shtml
- Mustang - http://www.mustangseats.com/yamaha/roadliner/roadliner.shtml
- Pacific Coast Star (PCS) - http://www.pacificcoaststar.com/pcs/roadliner_seats.htm
- Ultimate - http://www.ultimateseats.ca/yamaharoadliner.html
- Beadrider - http://www.beadrider.com/
The Ultimate appears to be the overwhelming favorite on the Star Stratoliner and Roadliner forum.
Several people have also had their stocks re-molded, shaved, and had gel pads inserted.