With that sensitivity rating you Should be ok. If you buy them some place with a 30 day return policy then you will be safe.
The 75 W of the Onk wouldn't SEEM to be nearly what those SEEM to want, but CV stuff is made for the low voltage Receivers that sell around them.
A better way to use the Onk and your money MIGHT be a "decent" pair of two way bookshelf speakers and a decent Sub.
Swan Diva 2.1's with stands run at 500.00 and mated with a good sub they will be a very good pair to grow with. There are many others.
My Outlaw is running a pair of Vandersteen 1C's rated at 90db sensitivity and there is no problem, but they aren't pushing a 15" speaker, only a 10" and their recommended max is only 100 watts. But the Vandy's go down to 38 Hz and a Sub can take everything from 60Hz down anyway. Running the Vandy's as "large" they sound quite good on their own and a Sub isn't needed for music at all.
Now why would the Vandy's, with only a 10" woofer and maxing at 100 watts cost twice the price of the CV's? There's a head scratcher?!?!?

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"Art is not a mirror, but a hammer."