And why do you think it's impossible to convert the VSPS to single rail operation? It's really just a bog standard op-amp preamp with carefully calculated feedback components to do the RIAA. If you compare it with any single rail design you'll see what's required - basically, just a couple of resistors.
Lots of stuff on single rail operation here:
https://tangentsoft.net/elec/vgrounds.html
Of course, there are advantages to using a dual rail arrangement, and it keeps the component count down.
There is a link to the VSPS circuit in #22 for anyone getting lost.