Hi,
We seldom use kVA here in the US, so I had to look about a bit. Generally you allow a 20% overhead except in the case where a surge occurs for a motor start situation. Basically you have three motors that could all potentially start simultaneously. This would indicate, if I remember right from my electrical training that is over thirty years old, that you ought to figure a load of about 60-67% of rated capacity. It appears that your choice may be sufficient though all wattages have not been give.
A site I happened upon, using kVA to boot, addressed this. It is Australian, I think< so may be more apropos:
Macfarlane Generators - Gentech Generators from 4 kVA to 16 kVA
Peace,
Clarke