If you want to pole out the whole Genoa, you need the length of the foot, or thereabouts. That'd be around 6m on your boat (4m "J" * 150%). A telescoping pole is the only sensible way to deal with this and still be able to store it and also gybe it.
Alternatively, you can use a shorter pole, the length of your "J" measures (around 4m) with the Genoa partially furled. Less drive of course.
We use a Selden telescopic pole that extends to 5.9m I think, although it was outrageously expensive. The poled out Genoa makes a good light air downwind solution (if you don't have any other sails for that), but it's a bit of a dance to set it up.
At additional cost you can have it on a mast track (easier to set up that way and stores flat on the front of the mast).
