STOP! My first suggestion is find some really low priced ’good enough to get by’ cables all around.Blue Jean cables are a possible choice. Cables made with Mogami wire, Canare Ok too. Cheap is the word. Any cables you can scrounge up for free? GREAT!!
Get to KNOW you equipment. Listen to it. get to enjoy it before jumping into the madness of aftermarket cables.
If you think, Jeesh I want more from this sound.. THEN yeah, start looking. Not now.
After a few months (really!) after awhile then decide which area you think you might be interested in.
A power cord, or IC, or speaker cables? (Seriously using a good ordinary cut up extension cord can work GREAT Cheap, and good enough for a long time. really $15...) I have $$$$ system, and have used eBay 0$0.30 ft wire for my speakers. Works great, sound pretty good.
For the wall duplex? Pass & Seymour heavy duty 20 amp $4.99
https://www.amazon.com/Pass-Seymour-Specification-Heavy-Duty-Receptacle/dp/B008SBH18M/ref=sr_1_6?ie=...or for a lot more money and a tiny maybe gain: Hubble $25
https://www.amazon.com/Hubbell-HBL5362W-Duplex-Receptacle-Industrial/dp/B000LE6N56/ref=pd_day0_hl_32...Anyway, good luck.