where can i find one?

Contacts will cover them up. I don't know of any other options myself, but more experienced modders might.
ChickieTeeta's posted Flajko's contacts converted for medieval, but if you have another set of sims3 contacts in mind you can convert them the same way hair is converted in the stickied tutorial- just label them 'blush' or similar, since medieval doesn't have all the makeup options sims3 does. contacts won't require any resizing between games, unlike the hair, and any texture oddities- if they arise- can be fixed by editing the dds files.

got it, but meanwhile i got another problem. the eye shader makeup seems to constantly revert back to the default grey color, for all sims. any fix for that?

Using saved custom eyeshadow colors seems to work for me.