I noticed that the ARRL just opened up the process for obtaining a certificate for Centennial QSO Party operation, as well as the W1AW WAS certificate or plaque. Go here: https://centennial-qp.arrl.org/index.php Use your LotW username/password to log on, and click on the “Centennial Points Challenge Award” or “W1AW/WAS Award” tabs along the top.
The certificates are $16 each, and the plaque is $60. The certificates looks something like this: