Not sure you are going to find much in the way of manufactured gassers with stepped hulls much shorter than 50". None spring to mind.
The Bonzi Edge is a stepped hull a little longer but a gasser available RTR or just the hull.
https://www.bonzisports.com/boats-rc-boat/50-bonzi-edge
Their fountain is a tad longer -
https://www.bonzisports.com/boats-rc...untain-rc-boat.
I am not sure the configuration of lifting strakes for either hull though.