Wow, did they give you this all in writing? The span between you keeping the car or giving it to them is way larger than normal. Usually salvage is sub 10% of value.

In any event, look for the Copart / IAA auction in your area as that is where the car will likely turn up. The only way to find out what it sells for is to be viewing the auction in real time so use a screen capture or vid camera to record the activity.