We have a 264, this option is available from the factor or dealer installed.
Since we back county camp, I have the dealer install the risers before we took deliver, so I can’t comment on towing before, but we have not had any towing issues..
The risers are not available for the following;
Axle Risers (N/A SV300, SV301,
SV302, SV303, SV304 & SV305)