Assuming you are only operating at low power, a few tens of milliwatts then a small core will be fine.
I usually use the circuit in figure 5. You can use the turns given, it will work, but in your frequency range I would use 3 + 3 turns instead of 2 + 2. for the split.
Ignore the capacitor you will not see any improvement by using it.
For core type and number of turns see post above.
Fairite 2873002302 or 2843002302 will work.
For wire size so long as it will fit the core you will be OK, somethiing aorund 28 AWG or SWG will work fine. It is not that critical.
Peter