Cubase SX

Hello all, new to this forum. I put recording on hold for the last 10 years but now looking to dust off the equipment and start up again. I still have Cubase SX running on Windows XP! The computer still runs like a champ since I dedicated it only for recording and never went online with it. Unfortunately I am using out of the box effects/plug ins and never upgraded. I was wondering if there was a way to still get a stepped up mastering plug in/program for this version? Also looking for better effects. Any help is appreciated!