I've been talking to Sean (worked for OCW and played polo) and he told me that the Mallet Heads Dan got, well the same company is making the poles for it as well. I'm going to talk to Dan and I'm going to get one in to see what it is like, so this will make it easier to build mallets as they are made for the heads.
They cost 10 euros so I don't know what that is in pounds, but guessing about 7-9 quid. Please correct me, i'm most probably wrong. :)
If your interested let me know then we can save on shipping cost.