I bought an Anker car charger on Amazon for $9.99 and it's quick charge.
http://www.amazon.com/dp/B00B8M4IMK/ref=cm_sw_r_udp_awd_9V6zvb0T1S6EP
Also bought the OEM Samsung adaptive fast charging wall adapter on Amazon with two USB cables for $16.
http://www.amazon.com/dp/B00TQZ3Z8Y/ref=cm_sw_r_udp_awd_XU6zvb1QY2BAD
Personally, I use the Blackberry Folding Blade chargers. They charge substantially faster than the stock Nexus charger+cable, and are very cheap. They are a 1 piece charger though, but have a 6 foot long cable attached.
You can read my review here (bunch of pictures, performance/charge time, current ratings, places to buy for cheap, and other people's experiences): http://forum.xda-developers.com/google-nexus-5/accessories/hands-best-fastest-cheapest-nexus-5-t2729066
If you want just a cable (and yes, the quality of the cable is VERY important), I think the Motorola Ecomoto cable is the best microUSB cable you can buy, It's built like a tank and supports a high current. I made a video comparing the Ecomoto cable, to a generic microUSB cable a while back. http://www.youtube.com/watch?v=wGYkt4CeYuk If you live in the USA you can buy it for pretty cheap from here: http://www.a4c.com/product/motorola-skn6378a-micro-usb-data-cable.html Outside the USA and shipping kind of kills the deal.
For the car, I use an Anker Car Charger + moto cable. It charges just as fast as the stock Nexus charger/cable. I can run GPS, stream music, and have the screen on the whole time and it still can slowly charge the phone. It's an older 18W version, but they have a newer 24W out that is highly rated as well.
Or if you want the Anker charger with a built in cable so you don't have to worry they have one as well http://www.amazon.com/Portable-Dual-Port-Technology-Lightning-included/dp/B00B8MMZY8/ref=sr_1_4?ie=UTF8&qid=1403589254&sr=8-4&keywords=anker+car+charger $9.99