Choosing components-Motor ESC Battery pack

Hello all,
I am new to this forum. I just looked at some threads and it is really useful!
I plan to build a DIY jet surfboard and i am on choosing the components.
The only thing i have now is the 64mm jet from MHZ Watercraft.
I have an eye on the following components now:

For the battery pack, i would buy that lipo battery two times and put it in series.

What is your feedback about all this?

Thanks a lot in advance!