Huskies are great "pack" dogs but not always great with puppies particularly of other breeds.  And they are very prey oriented as well as primal in their behavior.  They love to play, and they play very rough...wrestle/bite and make noise. 

Border Collies are not great "dog park" dogs meaning they don't play well with others.  They are the organizers of the dog world and very much "control freaks".  Keep this in mind as you'll need to select a BC puppy with a high level of pack drive and perhaps a lower level of prey drive and dominance in order to achieve a successful relationship between the two dogs.  Border Collies and Huskies play very differently from each other which may drive them both crazy as well.  (I have experience living with both breeds at the same time)

Also, owners try to interfere way more than they should.  A 7-9 week old BC puppy won't be able to walk long on a leash if the breeder even taught it to walk on a leash.  But the best thing to do is simply put the two dogs together in a neutral environment with a nonchalant attitude.  Both on leash if possible and take a walk.  Do not have them watch each other at a distance and slowly put them together!  This can further incite excitement and drive and create some tension when they finally meet.  Instead approach at an angle so they meet side to side.  Or allow the the Siberian to approach the BC first.  Keep the Sibe on a leash, but try not to restrain it.  (hopefully it's been trained not to pull on the leash)  But the best thing IMO is to get them both engaged in an activity other than each other.  Then take them home.  Always supervise in the beginning simply due to the size difference.  But try not to interfere.  Siberians are great communicators with other dogs (as are Border Collies).  They will work it out between them.  However be aware that it won't always be the Husky who's in control!  When that Border Collie grows up he/she may well take over as leader.  That's not something we can determine in advance nor something we should try to determine!  :-)   Alot of people think the first dog should remain the "leader" but trying to maintain that position if it's not the natural position of that dog is what can cause problems in the future. 

And by the way - I have taught my dog to walk on a treadmill, and what a great help it has been.  Great on rainy days, and since I have an arthritic hip and cannot walk for a hour at a time, I find it a great suppliment to energy draining - even though I still walk my dog every day, he is a happier dog when he's a tired dog.