I'm a book seller and have a storefront in Amazon and also have another store outside Amazon. I'll like to show my Amazon books in my other store with proper link to buy directly trough Amazon, is this possible using Amazon MWS? Any sample using PHP?
It is possible. Using Amazon MWS - you need to use the Amazon API with PHP - It would be not entirely complex to do; but making a plugin for Amazon, eBay and Opencart direct management of uploading and sync for multi commerce has always been on community pipelines. No plugin exists at the moment; free or commercial; you have to do this yourself.
1 - Make a new multi store in opencart.
2 - When adding products and assoc products to stores, make certain products available in your normal shop, and your amazon "multi store".
3 - In template files, if the product is on the multi store, pull the details and change the URL redirects with affiliate link and API link to Amazon cart.. it is a bit messy but for a quick solution..
Alternative is to create a native app for opencart.
Someone did this via a freelancer site; worth speaking to them:
Google Cache of Mayoousa Amazon Store and Amazon Product Feed Integration PDF
Or edit this (or uses code bases from this):