Code a Simple Wordpress Plugin

I need a wordpress plugin coded that will give the user the ability to generate what I call a "Thank you Redirect" Page. Basically it is a page that shows the custom message which the admin has entered for a specified amount of time, such as 10 seconds. Whatever time (in seconds) that the admin has specified when creating the page. Then after the specified amount of time the visitor to the page needs to be forwarded to whatever URL the admin specified in the "URL to forward visitors to after specified amount of time" field that needs to be presented at page creation. On the page that is generated below the custom content section there needs to be a .gif graphic of a "loading" bar or circle so the visitor will get the impression that they need to stay on the page as something is coming. I need the admin creating the page to have a few options of these images available for them to choose from when creating the page. I will provide these graphics (seen attachments). This image needs to be centered and just below the custom text. The admin needs to have the ability to choose "no loading graphic" as well. I also need the plugin to be secured in this way: after the plugin is installed and activated the admin is required to enter their paypal Transaction ID before they gain access to use the plugin. This is to prevent stealing or sharing of the plugin without permission. Please give me a quote on this project as well as how long it would take you complete. I do not have a large budget.