A high amperage adapter, 3A, and only 3.3V DC wouldn't be a very common adapter. The 3.3V DC is odd enough, although 3V would probably work too, but typically you wouldn't see anything much higher than 300ma.
I have the US version of the MovieBox USB. I bought it years ago and it came with Studio 9 which is how I ended up being a Pinnacle "fan"
I haven't used it in years because I quickly found out that capturing as mpeg-2 is not the best way to go. I soon switched to firewire capture as avi files. Before you invest a lot of time, and possibly money, into finding the european adapter, you may want to re-consider how you want to capture your video files.
Joe
P.S. here's the model info on my adapter. don't know if any of this will apply to the european model.
model: DSA-S15-03 A
p/n: 41002400
mfr: DVE Dee Van Elec.