You can try to use the REST API
To find a list of all landing pages with a specific name, in this case one that contains "Unsubscribe".
Depth, Count and Page have been included just so you know they are available to help you filter results
Eloqua instance in this example is on POD 4. If you need to check your POD here's a doc.
If you then wanted to you could also get information specifically on ID (3) found via this method and then use this call
Hope that helps