Just got this puppy in the mail today. For those curious about it: very worth the cost. It'll take a tiny bit of work to look SA, but I'm not at all disappointed in the purchase. I'll update this thread as I work on fixing it up!
I have made the grapple pieces available through Shapeways. A couple notes: I'm not sure they are the right scale for your grapple (I made them to scale with my own grapple model). They are not designed with moving parts. The tines must be glued into position. I made one open and one closed for myself. There are 4 parts to make 1 grapple dart... 3 tines and one shaft. Finally, you can find them on Shapeways by looking up 13doctorwho.
Your welcome to try them, but I really need to improve them. So use at your own risk (or not). good luck!