I have a Tapmatic head I have never used. It's the NCR50 and goes for $933.00 at KBC Tools. I'd part with it for $400 It can run up to 1/2" and 2500 rpm and the reversing ratio is 1:1, unlike a lot of tapping heads. Mine has a 1" straght shank. These heads are known to run into the hundreds of thousands of holes before even being serviced.
www.kbctools.com, page 138, p/n #1-415-36625