There are some townie and npc makers at mts (haven't tried them myself yet)
http://www.modthesims.info/download.php?t=216865
http://www.modthesims.info/download.php?t=178120
And over there you can also find a lot of face templates, which will produce prettier npc's if you kill them 
I really like these ones:
http://www.modthesims.info/download.php?t=250376 You should read the part with the "interesting links" they lead you to some tutorials on how to clean up your neighbourhood and get rid of your old npc's!
http://www.modthesims.info/download.php?t=229016

Oskarone provides some ray-bans for download. http://oskaronesims.webs.com/sims2accesories.htm
Scroll down to the bottom, it's the last accessory. Ok, I just saw that you only want the aviators, but you might like these anyway.

I've seen some recolors of that mesh at kieda sims http://kieda.net/?cat=284
There are also some red recolors, it's hard to say if it's what you're looking for without a picture...

Oh wow, thanks for so much support!      I think I'm gonna try Twojeff's Sim Blender.
So far I've only used sim PE's sim surgery, which was a bit complicated... hope this will make it easier. 

Ok, I didn't try it with insimenator, as this is just a bunch of hacks as far as I know  but I guess you mean simPE...
But I found some interesting stuff over at mts2 on how to make ugly born sims pretty (if anyone else is interested):
http://www.simswiki.info/wiki.php?title=Game_Help:Baby_Face_Problem
and a tutorial that contains the sim surgery part with simPE: http://simpeforum.ambertation.de/sims2/SimPE-From-The-Ground-Up-Tutorial

Hi everyone!

I'm looking for a hack or device that allows to make just the same alterations in a sim's face ingame as in body shop. My problem with in-game born sims is, that their cheekbones are always much too low, but with that plastic-surgeon career reward I can't fix that! (So they all look extremely crappy btw )
So is there a hack or sth. so I can do the same changes with their faces as with body shop?

Thanks in advance!