Summit Source still has some. Combine with your present antenna with a UVSJ like the code diagram in post #17.
http://www.ebay.com/itm/AntennaCraft...-/221387209204
http://www.summitsource.com/antennac...00-p-6310.html
Spec sheet for Antennacraft CS600:
http://www.antennacraft.net/pdfs/CS600.pdf
Disclaimer: I can't guarantee this will work, but it's worth a try. Antennas don't always survive shipping; about half of the antennas that I have ordered arrived damaged. Some sellers charge way too much for shipping. I wouldn't mind paying extra for shipping if they packed it carefully, but don't count on it.
If you can't get one from them, you are left with a custom made (expensive) antenna for channel 6, a DIY like the folded dipole I suggested, or an Hourglass Loop antenna designed by holl_ands, who is an RF engineer that does computer design of antennas.
The CS600 has 2.3 dB gain on 6. You could get that much gain from a DIY folded dipole antenna with an added reflector element, which is 5% longer than the dipole.
http://users.wfu.edu/matthews/misc/dipole.html
DIY Hourglass Loop for CH 6:
http://imageevent.com/holl_ands/loop...lassloopnorefl
http://imageevent.com/holl_ands/loop...ssloopreflrods
Custom antenna:
http://www.abilityhdtv.com/product-l...pg1-cid49.html