Searching for a wagon chassis

[ohlavache]

Hello.
I'm looking for a 4-wheel chassis with a floor of L2.5xW1.2cm. The floor length cannot be longer (but the overall chassis can be longer when taking into account the space for the coupler base); the width can be slightly larger or narrower. And the chassis should be as thin as possible.
Couplers can be either Rapido or OO9/HOe lifting loop.
Would you have any suggestion?
Thanks for your help.