Need php script to retrieve response from ebay's Post-Order API

General information for the business: We have an ebay store
Description of requirements/functionality: I am requesting someone's help to retrieve the json response from ebay's Post-Order API, Get Return call. We need to request the return details for each return associated with a specific ebay username and return the json associated with each return.

Here's a sample of the call and json response:

http://developer.ebay.com/Devzone/post-order/post-order_v2_return-returnId__get.html

You will need to already have ebay credentials to test the script. I would like it to return as much information as possible.

Please reply explaining the specific experience you have in relationship this task and what you're understanding of the requirement is. If you have experience, this task should take no longer than an hour to complete. If you do not it may take 2 to 3 hours of research and understanding and then no more than an hour to actually write the code if you are doing so from scratch. Again, you will have to have the ability to write and test the script using your own ebay developer credentials. Also remember, you are just requesting the return details for each return associated with a specific ebay username.

Please let me know if you are capable.
Specific technologies required: PHP, JSON, EBAY API
Extra notes: