The M14.ca (site sponsor and a Canadian manufacturer to boot) "black arrow" guide Rod is very nice. Works with USGI or Chi-com springs. Has a very nice durable finish. There are however 2 downsides; 1- some rifles require fitting. 2- it's costs $50. That said, you do get what you pay for. I have 2 personal rifles that are running black arrows
Stay away from the Marstar style stainless guide-rod. It's pretty, it's fluted, it doesn't fit some Chinese springs. It will require fitting to your rifle. (I have yet to see one that was a drop-in fit). I have 3 or 4 of these in the "NFG" bin..... All have been altered and are marked up and/or show signs of galling. A terrible product, IMHO.
There are several options out of the US. Most in that $45-$60 USD price range. Most are pretty good offerings, but may or may-not require fitting.
Personally, I prefer the S&J hardware (site sponsor and a Canadian manufacturer to boot) guide-rod and spring combo. It comes with a very good recoil spring (the factory Chinese spring is garbage. The Chinese make good steel, but can't seem to make a decent spring to save their lives) and it costs about $50.
I like the S&J hardware product so much, I include it in my package pricing. It's hands down the best bang-for-your-buck guide rod combo available to us Canucks. I have 5 personal rifles running a S&J combo.
Cheers!