No, the Huntsman forend will not fit the Sidekick without some modifications. It would need a new hole, and it would have to be opened up in the rear of the barrel channel to accomodate the swell near the receiver. The Sidekick has a shorter receiver, so there is more material removed from the forend since the barrel profile is still the same as the Huntsman. I think there are pics in the FAQ's that if you study close, you will know what you are up against.
Do you mind disclosing the place that is selling the walnut stocks? If these are 95%, can you explain the other 5%? Finish? Recoil Pads? Hardware?
Yes, these NEF's can be shooters, I have shot several MOA groups with mine.
Huntsman is on top, Sidekick on bottom of pics. You might be able to see what I mean from my pics.