I need to setup a live subscription or cronjob to get order item details like status, amount and sellersku etc but I cannot find any such subscription API for this and getOrder API only permits 6 consecutive requests before being throttled.
Please guide me with any such API.
If I understood you correctly you are trying to retrieve orders from Amazon for fulfillment. This can be done by scheduling a _GET_ORDERS_DATA_
report to run at a certain interval and then acknowledge, retrieve, and process the report.
http://docs.developer.amazonservices.com/en_US/reports/Reports_ReportType.html