I am running a BMC CDA intake. Its a sealed unit and sucks air from the passenger side bonnet vent. Works well, well better than the open filters.
from what I've the read, the best inatke for the R53 is the JCW Airbox with a performance (Alta/K&N) filter.
You can buy the BMC locally and it costs I THINK around R2K. Any other aftermarket you going to have to import.
Also try
www.outmotoring.com. They have Alta Intakes and whole lot of other goodies. I have bought from them and they service and delivery times are great. They are safe also so you can use your Credit Card on their site. i havent had any isssues yet.