We got a box at WDW a few trips ago and then we got another box at DCA about a month ago. I saw quite a few of the same things WDW has, and some new, but they may have them at WDW now too. Also, as far as I know, you can't buy any of the parts ,that are sold by the box, separately. So if you see something you want, you'll have to buy a box full.
Also, a tip, if you don't already know-I bought our PH before we went so we were able to fill the box with only accessories-I got tons of things in that box.
If you do buy the head, make sure to open him up and stuff his insides too!
OT-Just the other day I saw a priates
set of PH at Sams Club. It included 2 big heads, 2 spuds, a pirate shaped PH carrying case, and many pieces-some pirates themed (also mermaid) for only $20. It is really cute! I wanted to buy it but my DD6 wasn't too interested. Maybe I'll get it for her 7th
anyway!
Here's the link if you want to see it
http://www.samsclub.com/shopping/navigate.do?dest=5&item=338577&pCatg=1137
it lists all the parts included.
Have fun-5 days until WDW!