There are so many choices that will be just fine. My one caution on used audio gear is that the receivers will just... stop sometimes. Speakers? Speakers can be reconed, etc.
I once had a stereo-file type buddy tell me "as a general rule of thumb, spend as much on speakers as you spend on your amp." I'm not sure how true it is... but it didn't sound like bad advice. That outlaw looks sexy. The KLHs.... I've seen/heard mixed reviews for them. But if you're "endorsing" them - they can't be all bad. I do love me some craigslist hi-fi shopping... funny enough, recently my amp has started to.... not stop sometimes. I'l power it off, and ten minutes, walk by and it's on again. The poor girl is 23 years old and has been beat up for a long time... it might be time.receivers will just... stop sometimes.
So reality check: I do my serious listening on a set of Genelec 1029/7060. I bought them all new, I bought them at cost, and that was like $2500 more than ten years ago. I do my casual listening on three Infinity bookshelf speakers and a pair of ancient Altec Lansing surrounds. I think the Infinitys were like $150 each. You know what? They're as good as the room. I endorse KLH because (1) they were never expensive (2) they were probably the last company to let go of the adage "there's no substitute for cubic inches." KLH are big. KLH are cheap. Big and cheap has much better low end response than small and cheap. This whole "2.1" bullshit is because nobody makes big, cheap speakers anymore. If money were no object, I'd probably go Martin Logan. They can be had not too expensively on the used market. Honestly, if money were no object I'd have Genelec 1039s but those you pretty much start with the speaker and build the room around it. Barring that, a pair of Klipsch corner horns would be pretty dope, too... but I do far more watching than listening and that means I need a center channel and an unmatched center channel (which every center channel you've ever seen is one of) fucking sucks which means I physically cannot listen to 5.1 with corner horns because a corner horn that isn't in a corner isn't a corner horn. I'm firmly of the opinion that 90% of speakers out there are pretty much better than most people need. As far as receivers: There's no shortage of cheap, effective stuff in the land of Class D. My typical advice is to go to the store and buy the one with the remote that makes the most sense. I used to endorse Harman Kardon until I had one die on me after 13 months. I used to endorse Denon/Marantz until I, along with everyone else, ended up unable to listen to surround out of a Chromecast for some stupid reason (Apple TV and PS3 are fine). The HK, prior to death, would just start ramping up the volume, 1dB per second, until it blew up speakers. It was one of the least friendly failure modes I've ever encountered.