I was in the same predicament as Nisse when I first decided on the concertina as my instrument of choice. Located in Bermuda it is impossible to find any instruments to try or rent. I had hatched the idea of trying a concertina and had to wait months before a scheduled family holiday to the UK before even seeing one in person! I remember being adamant that I had to be at John Dipper's workshop on the English Concertina at Sidmouth folk festival and diligently showed up every morning for class. John was the person who recommended that I try the Anglo as I wanted to play Irish music and possibly the odd Morris tune. I ended up trying Anglos all over the festival, and was completely blown away by the pricing! I settled on a Stagi 30 button - maybe I should have gone with a Lachenal 20 button. I had never even played an Anglo at this point! I picked up Mick Bramich's tutor and have never looked back. I have no opportunity of playing with other Anglo players unless I travel to other countries, but that doesn't hold me back. Maybe my techniques not perfect, but I have a great time and it's forums like this where us isolated concertinists can at least feel a part of the free reed world!
I have to say that after six months of playing the Stagi became a bit of a hinderance to playing reels upmto tempo. I ended up ordering a Morse Ceili - purely based on customer reviews. Again there was no chance of trying one! I was not disappointed. Sure it would be great to be able to play an authentic reeded concertina, but my Morse can do everything I need it to do and now I'm the only hinderance to my own progress!
I have to also recommend the Skype lessons offered by Jody Kruskal and other top players. For players like me the Internet is a treasure trove and technology allows us to connect. I have been taking Skype lessons with Jody and the quality and personal instruction are more than worth the investment.
All that to say that if Nisse takes up English, Anglo or any other system, she's joining a great community and starting on a very interesting adventure. Nowadays, being isolated from other players is inconvenient, but not insurmountable!
Good luck!