Boat seat replacement help

[Paradactal]

Has anyone replaced their seats on an older Nitro Savage 896? Not looking like there are to many options out there that will fit my boat well. Im looking at the 57" bass seats on Boat seat store. Taking measurements, it looks like the 57" may be a touch to big (wide) in the center. My boat has the built in step that makes things a little snug. Id hate to drop $600 on seats that dont fit correclty. There has to be someone who has replace these seats. Picture is not my boat, but same setup. I have 2 little kids, so it is important I have the 3rd bench seat instead of the console, for now.
Seats Im looking at

 

[Pat Dilling]

Check here too: Bass Boat Seats

 

[Kerz]

Cant help on the replacement seats. I can add that a new rear fishing seat for my Z18 is $500, way too much. Just a little perspective.