You don't mention a budget range, but the Bessa R3 (A or M) would probably allow fairly accurate focus. In general, for 90mm focal length on a rangefinder the longer the base focal length, the better (more accurate) your ability to focus. If money is no object, how 'bout a .85 Leica M or a used Leica M3?
For any longer then 50mm lenses M3 is probably the King. Focusing is so much easier and snappy then in any lower magnification cameras and that is the real asset for long lens wide open. I found my 90mm Elmarit is joy to focus on M3, much faster and clearer then on x0.72 M6. Having said that, x0.72 M6 aslo works fine and allows precise focusing even wide open with 90mm lens, albeit with probably some more effort on you eye during focusing.