I cannot help you track down one of these beauties [and I certainly WILL NOT sell you mine!], but I encourage you to keep up the quest.
$1700 seems a bit high, even in mint condition. There are 3 on eBay currently for $1200-$1450 shipped.
FA* lenses are so good that current owners probably think long and hard before putting one up for sale. That's my theory anyway on why they seem to be so rare & pricey. One would have to dangle alot of dough in front of me before I would consider parting with mine!
I started shopping for a FA*28-70 after being pretty much underwhelmed by DA*16-50 performance. I bought one last May for $1072 USD. The FA* was not in mint condition, but optically it has proven to be outstanding. After a few weeks of shooting with this lens, I pretty much forgot the pain associated with FA* cost of admission. Selling the DA*16-50 a few months later also helped with that
These FA*28-70 jpeg shots are pretty much straight out of the K7 with no special filters used, then sharpened & resized to meet forum posting rules (which unfortunately kills the sharpness of the photos. The uncompressed 9MByte versions look fantastic on the 22" Samsung!).