Thank you all for the info...
@divemaster: unfortunately it is only for people living in U.K. - got thi smessage from them:
"Many thanks for your email. Unfortunately we are only able to provide this type of cover directly to UK residents therefore we will not be able to assist you in this instance."
@Wolfgang: I started to negotiate with this insurance (Uniqa). The fare is 11% of the equipment value, so in case the equipment is worth 15000 Euro it is an annual fee of 1650 Euro. Seems to much to me (I think that probably not the netire equipment will be stolen or flooded at once and the actual damage sum will be considerably less). I think I will bear the risk on my own then...
Interested to hear how others deal with this risk (insurance or not? what rate? how much coverage?)
Edited by Architeuthis, 08 August 2018 - 10:21 PM.