Stands are from Games Workshop – my local shop didn't have them but I was able to order on line. They do two sizes, these are the smaller ones.
The plane and stand both have a neodymium magnet – I got mine from Dom's Decals.
The banking thing is very simple and when I thought of it I was amazed not to find any evidence of it being done before. All you do is cut the top end of the vertical peg off at an angle. I used a razor saw and a simple jig. I can't recall what angle I went for. Probably 45 degrees. This sets your magnet at an angle. I used a very small blob of two part five minute epoxy to glue on the magnets to the planes. These Raiden models have a little hole under them so I just filled this with epoxy and popped the magnet on top of the little bump of glue. I think I used gel superglue to fix the magnet to the stand. This system is neat as you can use standard magnets that are small and visually unobtrusive and you don't need to mess about with ball bearings etc
Once you have mounted your plane on the stand simply rotating the model will give you climbing, diving, banking or a mix of two. Honestly it's so simple and there is no need to buy those expensive stands with angled heads unless you want to show your planes inverted.
You can see the two magnets under the Spitfire and the angled top of the flight stand peg on that pic I posted.
I have my bombers flying straight and level, on the larger sized GW stands, but if you were able to buy bigger magnets the idea should work for those heavier models.
The Magnets from Dom are powerful enough for planes up to a small twin eg, Me110 but not a medium bomber like the He111.
experiments to find a better way to mount aircraft for wargaming.