You can go to a community like sinandsalvation and put up an ISO (in search of) post. You'd just need to say something about being in Germany, not wanting to pay more than the original cost of the bottle ($17.50) plus shipping costs (which is usually $4 internationally) and that's you're new to BPAL but the empty you received was just perfect on you and you'd like an actual bottle of it.

People only take Paypal, and usually ask that you chip in on Paypal fees (about $0.50 or so). sinandsalvation is a great community as no one will gouge you on prices (they have rules against that).