Have you tried using a MT truck with long shank? I used MT-1038 (003 02 044) for my Atlas articulated autoracks (their accumates are lousy) and they work fine. Alternatively you could use MT body mounted couplers which will entail some work.
Cheers,
If you go to the microtrains website, you can access their conversions chart.
www.micro-trains.com
I didn't see the bi-level cars listed, but for most other passenger cars they list the #1130 as the rapido replacement.
That's the old number, the new number is #001 30 014
Hopefully that will work for you.
Craig