Chain Guide

Try a skateboard wheel until you get a new one.

You can make your own from teflon cutting boards, I have not worn out one teflon roller.
 
Get a ball bearing chain roller. I ended up buying an Alba roller off of ebay. It came with the bolt, so I used a hacksaw blade to remove the stock post off the frame. I cut the post flush with the frame and then just threaded in the bolt and it works great.