Well, your head is
1000W @ 4 ohms
600W @ 8 ohms
And that cab is rated
500W RMS, 4 ohms
You can't really "mismatch" a cab to a head, per se...
However, you can smoke your cab.
It's fine to use that cab with your 7pro, but you need to be careful with the volume and turn down if you hear the cab struggling.
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