Good battery that you can order from Germany

Hello there!
I think the battery of my GT-I9305 broke (it doesn't boot or charge but gets warm if I put it into my USB-port and let it there for some hours, so I don't think it's the mainboard or something like this) so I want to order a new one.
(I'm testing it out on monday.)
After some time searching for a good one on Amazon and Ebay I wanted to ask you, if you know a good battery that you can order from Germany without paying tons of shipping.
I found one on Amazon from "mumbi" but there are some good and some bad reviews and I really don't want waiting for a replacement... My iPhone 4 is so terribly slow, I can't use it any longer without getting a heart attack because I'm so angry... :p
I think that I don't need much more capacity than the original battery but it would be good if I could use my phone 3 hours minimum without charging it (that would be a dream to be honest, I'm familiar with 1,5 hour maximum...).

Anyone from Germany here that can tell me a good battery? I would be grateful for life!