I found this on the Pentax Peru Facebook page:
Página creada por Foto Panamericana de Perú S.A.C (Representante de la marca en Perú)
Para mayor información comunicarse al 4701469 - 4708798 -4700938
Direccion: Nicolas Arriola 401 Santa Catalina - La Victoria
If they don't have what you're looking for try MercadoLibre and OLX. I've ordered photo gear from ebay and had it shipped here, including a lens from Japan that included free shipping. In my case it was cheaper to order direct from the manufacturer and pay the customs duties then it was to order from MercadoLibre.