Why don't you contact S+S yourself and ASK? AFAIK S+S doesn't do frame mods, they just make the couplers. You'd have to locate a framebuilder and discuss the issue with them.

Typically coupler retrofits cost upwards of $500, not including a frame refinishing which can cost several hundred more. Add another $150-400 for a case and padding to transport disassembled bike.

Couplers are an expensive option on new frame builds, and cost prohibitive as retrofits.

Some coupled-frame owners have opined that it is a PITA to disassemble and then reassemble their bikes, so they ship them in large bike boxes instead.