Stuck with matching input signal to an active filter
If you can't find a different component that fills the need: I would try to rethink the whole signal chain and see if you can get away with a lower voltage overall and just using an x2 stage at the end of it. A 3dB penalty on SNR is rather easy to compensate for and you could reduce power consumption by a factor of 4. You would have less overall error this way.

But otherwise I don't see any other alternative. But you don't need (or even want) an op-amp to do the initial ÷2. A passive network of resistors and/or capacitors is more than enough. That means that you only need 1 amplifier to get you back to your desired signal levels.

A matched resistor array that can be matched down to 0.1% or better would take care of most precision errors in both your divider and your amplifier.

To avoid loading the input resistive divider by the input impedance of the filter you have two alternatives:


Incorporate the output impedance of the divider into your filter design (preferred solution).
Make the output impedance of the divider low enough to be of no consequence to the filter (would unavoidably introduce a systematic error that should be taken into consideration).


Regardless, you might want to use the output impedance of the divider as part of an anti-alias filter, which is advisable in any switched-capacitor configuration.