Override Django Admin URLs for Specific Model?

First a little background:

I have an Event model that has various event_types. I want to break one of those event types, 'Film', into it's own admin. I have the basic functionality in place: a proxy model inheriting from Event, named Film, a custom manager for that proxy model that filters it to only 'film' event types, and it's own ModelAdmin.

The problem is with the reverse. I now need to filter out films from the main Event admin. I don't want to alter the Event model or its default manager, because the impact would be too widespread. So, I tried creating another proxy model, EventAdminProxy, with the sole purpose of providing a filtered list of events in the admin. I then register this model, instead of Event, with the existing ModelAdmin.

This obviously works, but it has the unfortunate side-effect of altering the URLs in the admin. Instead of the changelist being at "/admin/event/event/", it's now at "/admin/event/eventadminproxy/".

What I'm trying to do is keep this setup, but also keep the old URL. I've tried overloading the ModelAdmin's get_urls method, but from what I can tell, you can't control the full URL there, only what comes after the "/app_label/model_class/" part.

I thought about overriding it in the main urls.py, but can't figure out an acceptable view to tie into. The actual views are only available on the instantiated ModelAdmin object, not the class itself.

Any ideas of how override the URL being used in the admin?