I would not recommend using a wire slicker for a Hav puppy. It coul scratch the puppy's skin and hurt. You want to havw positive associations with grooming as you will need to comb and brush a lot down theyears.
So, you will need a comb and pin brush, shampoo (no tears formula for puppies) and conditioner. I bought Johnson & Johnson Baby Wash specifically for my puppy's butt baths.
I cannot give too much feedback about ex-pens. You may want to search in the puppy forum (using different spellings for xpen, ex-pen, exercise pen, expen, etc). I went to Babies 'R Us and bought a 6-panel plastic 24" high play yard, and my dogs never climbed or jumped out, but my sister-in-law's miniature poodle mix was an escape artist, and we found her at the front door with my 2 dogs still inside the play yard.
I think most of the ex-pen/wire crate set ups use a wire ex-pen so that the crate can be attached to the wire panels. Check Tom King's thread about puppy house training. He has some photos.
When your puppy is teething, you may want to have special teething chews for him/her. One company , Petstages, makes great chew toys for puppies. They also make a freezable chew toy that can help with teething pain. I am sure there are other manufacturers, too.