I found AD3 drops. I think usually they are given to small kids, but you just calculate the amount of drops you need. I decided to take 18 drops per day which is just a little less than suggested by the protocol. I figured that I get the rest from food source (I am eating oat bran and vitamin D fortified milk). It’s fairly inexpensive for me as I need like two of the little bottles per month which amounts to barely few euros.