Kontera is a very slow earning process. It can take up to a year or two to actually reach their $50 dollar payout. So Kontera isn't your best bet. Also if you've been reading the forums on Hubpages you'll see that Kontera is mostly hated now because of how cheap a click is worth. Ranging from $0.01 cent to $0.03 cents. Not something you want to put on your content.
People more so avoid any Hubs or websites with Kontera ADS or Kontera Like style ads because of how annoying they can be. If you've ever went on a website and scrolled over a Kontera AD and it played a video how much resources it took away from your computer to play it so I would avoid Kontera all together and focus on Amazon.
Now Amazon can never fully replace your Google Adsense but it can make up a substantial amount of it. If you where to focus hubs on specific products from Amazon you can stand to make a lot of money like so many hubbers are doing now-a-days. I know of some hubbers who only do Amazon alone and are making good money.
So if you can't get Google Adsense and only have the choice between Kontera and Amazon, focus your hubs on Amazon products and hopefully you'll get a good amount of sales in that area. I wish you the best of luck and hope this has helped you out.