You may have a hard time finding a receiver in the aftermarket. I just checked the Reese website with no luck. There may be a member that is using the LR that can point you in the right direction.
When you check out the factory unit inspect the welds carefully, and a robust build. One of the first things I had to do on the 06 Burb was change the receiver.
Better to have more than you need than to need more than you have.
Keep us posted on the Stream search.
"Sticks & stones can break your bones...and hail will dent your Airstream"
So when is this..."old enough to know better" supposed to kick in?