Kailex will be cheaper for you to get a conversion cassette, the darn hub body is almost the same price than a conversion cassette from american classics for example.
I almost got a set of wheels fulcrum 5 last week and i was thinking on doing the same u mention and sort do not worth because of the cost. Besides looks like almost nobody have the fulcrum body available also.
Im running a easton vista shimano with a campagnolo conversion cassette right now and works fine.
I believe the answer is no. But, from what i heard/read u can use a shimano cassette with campy brifters and a sram rival RD, and that combination i read works fine, anybody knows something about this?
To tell you the truth i have use a combination like the one u mention but with no respacing and the only issue is that u'll lose a few cogs, for example 1 or 2 of the small ones and at the top also. from the 10 cogs u end up with 7 or 8 working fine just in case.