Rain guards are pretty much limited to whoever wants to sell their set. I got mine locally from BorHor. Put up a WTB and you may be able to convince someone to sell you theirs. I paid $100 for my set.
BTW, be careful with the taillamps. Most of them come from clips, and may have hidden damage. Mine cost me about $150 shipped from Jarco, Inc and were in great shape. Also, you will need 89+ USDM bulb boards (if you're 86.5-88) to keep the lamp failure light turned off.