Hi. Definitely check CL for the Splendide 2100xc vented unit.
We just picked one up last month for $250 that was barely used.
We checked the serial number on it and it was manufactured in 2012.
You can go online and there is a cross reference there to find out the date.
Also, Splendide has a scratch and dent dept. You could call and check if
they have any. Some RV Surplus stores have them too.
The scary part is installing it. It is still sitting in the 5r living room because I am freaking out about cutting a 4" hole in the side of the fifth wheel! Plus we are waiting for the temperature here to drop below 100 degrees.
We bought the vent, tubing, and hold down brackets on Amazon.
Good luck
C