If you are wanting the threaded Nylon rods like I used, I got them from Zorotools. IIRC, it was so cheap, it felt like they might have lost money shipping them to me. This is the rod I used: http://www.zorotools.com/g/00011121/k-G2163707/
And here are part numbers on some other parts I got from them:
G1044732 Black Threaded Rod,Nylon,3/8-16 x 2 Ft,UNC
G2163707 White Threaded Rod,Nylon 6/6,3/8-16, 6 Ft
G1062817 White Flat Washer,Nylon,Fits 3/8 In,Pk 20
G1308641 White Flat Washer,Nylon,Fits 3/8 In,Pk 40
G1722061 White Hex Nut,Mach Scr,Nyl,3/8-16,PK10