I installed a Milodon Aluminum high-flow unit on my '66 289 this past weekend -- seems OK, although the impeller was stamped, not cast /forums/images/icons/frown.gif. On the up side, it had that anti-cavitation plate on the impeller, so...
$75.75 from Jegs, I believe, with both gaskets and back plate included. Installed no problem.
Now the ARP water pump bolt kit I bought, that's another story. The bolts are great (12 point SS), but the sizes weren't really optimum for my install, which I thought was pretty standard. In fact, I had to re-use the bolt that goes in just above the fuel pump, as there were just not enough bolts of that size in the kit to go in all the places that actually needed them. Strange.