I built my own liplights for awhile, using LEDs bought from Mouser Electronics and moldable epoxy. They work, but I eventually went to a headlight. I bought one at the local megamart which has 2 white and one red LED. I don't like red at all, so I changed the red one to green, which I had been using all along on my lip lights. The headlight works better for me, because I can use it for preflighting, and the bright white lights are useful in the cockpit for getting things ready for the start, and the start itself. I use the single green light while flying, to avoid blinding the copilot. I've decided that trying to worry about preserving night vision is a waste of time, because all the cockpit lights are white, there is nothing to see outside while flying anyway, and on approach the rig lights are bright enough to destroy night vision anyway. On takeoff, the bright lights have washed everything out, and it's off into pure blackness, an instrument takeoff, so I've quit worrying about it. The liplights are, IMO, more trouble than they're worth, but some people do prefer them, and I believe it's a matter of whatever works for the individual.
Here in the US an office supply chain called Office Depot carries lighted pens which also have a PDA stylus, fairly cheap. For lighted pens in Europe, I have no advice other than Google.