...because due to their bipolar output voltage swing a bipolar supply voltage is needed, only for them.

Why not omitting the input buffers? Increase a bit the resistances of the passive voltage divider and give the input signal directly to voltage divider.

For the output buffer OPamps you can use single supply types with rail to rail characteristic, which means that they can handle an input common mode voltage range and output voltage swing that includes the supply rails.

Take care, in any case you will need adequate low pass filtering and some protection against overvoltages at the input (depending on choosen OPamp). Optimal would be an OPamp that can be driven by the same voltage as the micro (decoupled by some low pass filtering, of course).

Kai

PS. Their is more wrong than the polarity with your drawn output buffers...