JordiPlana

This plugin hooks the normal WordPress workflow in order to determine if the request is processing will cause a 404 HTTP error. In that case it prevents WordPress to do any other processing and sends the user to the page defined in the plugin options.
A working and simple solution.
For more information about this plugin you can check <a href="http://jordiplana.com/404-simple-redirect-plugin-for-wordpress" title="404 Simple Redirect Plugin for WordPress" rel="nofollow ugc">the official page</a>.

404 Simple Redirect

This plugin hooks the normal Wordpress workflow in order to determine if the request is processing will cause a 404 HTTP error.

PressPage Entertainment Inc

This plugin was developed to solve a redirection issue when navigating from a secured checkout page back to 
a non-secured page (or page that you need to have as non-secured—possibly because of non-secured 
external links, etc.)
For example, a user comes to your wordpress e-commerce site, locates an item, then navigates to your 
secured checkout page. Now the customer, realizes there is something else they need, and instead of clicking 
a Continue Shopping link, then click a top category link. Since the customer is in a secured session, wordpress 
put the secured protocol on all the links including that category. Now the customer navigates to that 
category, but they are still in a secured page session. Now this category page is displaying improperly because 
of some external links that did not translate properly into the secured session. Customer is now upset, thinking 
that the site design demonstrates the level of incompetence of the shop owner and questions the shop owner’s 
integrity to fulfill the customer’s order, so the customer in a behavior of discuss, rapidly leaves the 
shop owner’s site and that customer becomes a non-customer!
This plugin resolves this issue by redirecting all non specified checkout (and other non-secured pages) 
back to a non-secured page counterpart.
<h3>Credits</h3>
We make honorable mention to anyone who helps make Mavis HTTPS to HTTP Redirect a better plugin!
<h3>Contact</h3>
Support is provided at https://github.com/pingleware/mavis-https-to-http-redirect/issues. You will require a free account on github.com
Please contact presspage.entertainment@gmail.com or visit the above forum with questions, comments, or requests.

Mavis HTTPS to HTTP Redirection

Provides page redirection back to non-secured pages (https: to http:)

404 Simple Redirect vs Mavis HTTPS to HTTP Redirection