Walindi Plantation Resort and MV FeBrina recommend the following Spanish agencies, listed in no particular order.  The country code for Spain is +34.

Ultima Frontera 
Contact: Ramiro .. 
C/- Francisco Gervas,  17 7oH,  28020   Madrid 
Tel: + 34 91 571 8470 / Toll Free:  

Febrina is one of those rare nuggets of authenticity in a growing sea of fabrications.

Michael D. Crane AICP, Crane Associates Inc, Vermont - July 2015