You can't get the PCV valves on their own from BMW but the main one which is prone to failure can be replaced with the Rob Beck one. If you go on the other forum you will see a big topic on it with pictures and a how to guide.
I've not upgraded as my cover is pretty much new but I'm thinking that due to the high boost levels it might be wise. The check valve is available with the pipe which runs from the crank cover to the inlet tube.
What is your oil consumption like? Blue smoke is normally an indication of burning of oil so it could be valve stem seals, turbo bearings or PCV system.