I have one of these motors, a KD A22-20L, in an 800gram glider and it will keep accelerating in a vertical climb till it's out of sight! I have used a 10X6 prop the most but have also used a 9X5, a 9.5X8, and an 11X6. The motor runs nice and cool with all of them and I really can't say a single bad thing about it. I would not hesitate to use one in a glider that weighs 1500 grams or even a bit more. It has a 3mm shaft and even comes with a spare. I'm assuming that you are somewhere in Europe so, considering that shipping from GiantShark was very reasonable to the U.S., shipping shouldn't be a problem.
The KDA has very similar performance to the Turnigy 2836 that HoosierGuy mentioned. I also recently got a Turnigy SK3 2836-1040kv. I have only bench tested it so far but it turns a little faster than the KD A22-20L without drawing more current. In other words, it's a little more efficient but I haven't actually tested it in the air so I can't give an unqualified recommendation. Here's a link for comparison and note that it has a 3.17mm shaft just to keep things confusing.
Most spinners use a cone shaped collet that clamps down on the shaft when tightened. There's one in the picture of the 2830 motor you linked to. Some spinners come with an assortment of adaptors while others only fit one size. As one collects different props and spinners one will eventually find that some adapters are interchangeable or can be reworked if you have a little experience with basic metalworking. I'm afraid that I can't help you on finding a good European supplier but someone should have the entire Graupner line available and they are of very good quality so they probably end up being cheaper in the long run because you won't end up with mismatched parts.
I am using a couple of spinners from HobbyKing and they work well but I received some dangerously defective prop blades from them. It's only the one size of the one brand but I can not recommend a HobbyKing prop in good conscience. You can read about my experience here.
Also note that those motors with a 4 digit code like the 2830 and 2836 tell you the approximate, relative, power level. The first 2 digits are the can diameter and the second 2 are the length. All other things being equal, the longer motors have more power and are a little heavier. Then you get a company like KDA that uses a different code. Once again, they do all they can to keep things confusing!