Any Concertina Things To Visit In Berlin?

[MatthewVanitas]

I'm visiting my girlfriend in Germany for a month or so; depending on work and relationship, I might end up basing myself out of Berlin while possibly working some contracts in Africa and the Middle East. I've already got into contact with the Shape Note singing community here, and am looking into clavichord lessons, and picked up a three-row GCF diatonic accordion for €40 at a flea market. I don't have my concertinas with me since my Crane is in Colombia and I don't want to risk taking my Beaumont on the road, but if there are concertina things to see in this city, cool shops for squeezeboxes in general, or easy ways to get a hold of some inexpensive concertina variant here, I'm interested. Thanks for any ideas!