Is there a generic pattern for the redirect?
You might be able to add something in a .htaccess file that will redirect pages that follow a pattern or rule to another?
This may be a quicker option?
Alternatively, I would use one of the free online tools to create a google site map. This will generate an XML file of all the pages it can find on your website.
You could use this.
I'd be keen to see how you solve the problem.