I would be interested to know your experience with the fins you have tried, I have ordered size 10 boots aswell and currently have Avanti X3 size XL and have figured that I may need new fins, although according to the link they should be fine.
Turtles. Jets probably not big enough. I struggle with normal drysuit boots and jets, so I got some turtles. And they're lovely. If you can hang on then Beaver are bringing out some clones soon enough, should save a few quid maybe. Not that I approve obviously