eyebrow

How easy is it to change the eyebrow lights on my class? Was thinking about these bulbs http://www.autobulbsdirect.co.uk/501-W5W-Xenon-Extreme-White-side-light-bulbs.html

Hi everyone , I know this is probably a question asked by many but how can I get a set of white error free LEDs to go in the eyebrow sidelights for my 2009 W204 Sport ? Who from and how much and are they easy to fit? Cheers