For the turnout coils, I have decided I would have to check what current was necessary for it to switch. I tried to do some test with the multimeter, but due to the high current spike during the commutation and the narrow switching interval, it was not possible. No problem at all, I attacked the issue with an oscilloscope. The results and its schematics follow:
The first one is related to a no switching event, the second, to a switch.
After many days of research, asking for help to Alexis and Samuel, and hours navigation in Farnell and Radiospares, the best solution I have found was to use plain NMOS transistors with Schottky diodes. The ICs for driving relays are very expensive, don’t support enough current and come with functions our project will never use.