AH! Now I think I get it...you are living IN Portugal!?? If so, what a beautiful country you live in! I enjoyed visiting there back in 1999. I'm sorry that I did not realize that (if it is true) in answering your questions about buying tubes from abroad (so obviously your English is excellent and there is no need for apologies). There are many reputible dealers in Europe that have all kind of wonderful tubes available, and because you are over there (at least I think you might be) you should probably seek them out. Germany and Switzerland both have some reputable dealers and are not far from you. Anyway, glad to help you in whatever small way I could, but as I mentioned I cannot comment on the tubes you are interested in and will leave that to those with more direct experience with that tube type.
Good luck!!
Good luck!!