Yes, the Reporter license is perpetual, and therefore you can re-use it. The Reporter 8.x license will allow you to process up to 2.5 Billion log lines per server.
Here's what to do.
Find and edit the licenses.cfg file in the in this folder of your old Reporter server.
C:\Program Files\Blue Coat Reporter\LogAnalysisInfo
Cut and paste the license out of the file- It is the number in-between the inverted commas.
Login into your Reporter 9.x server and go to the Administration > General Settings tab.
Click on the "About / Licenseing" option.
Paste in the number to this text box, and press save.
You should now be re-using your perpetual license for Reporter.