Just thought I would share. Its not an advertisement, but I ordered a Selkirk double wall stove pipe (DSP) PN-266610 - 6" vertical installation kit for $114. $130 shipped, and had it in 3 days! Its the cheapest I have found online.
http://www.ronshomeandhardware.com/266610-6-Vertical-Install-Kit-p/872903.htm
Good Luck!
http://www.ronshomeandhardware.com/266610-6-Vertical-Install-Kit-p/872903.htm
Good Luck!