Firmware Update 2.20(AQU.6)C0 for ZyWall USG 200

Hi,
I'm trying to learn about Firewalls & found a ZyWall USG 200. I'm trying to find the firmware update 2.20(AQU.6)C0. However, since the product has passed the EOL, I cannot find this.

I know this device is very old & has passed eol, also, I'm not going to use it long term, but just to explore the features & get myself familiarized on basic concepts.

Appreciate if someone can share this firmware update, since I'm not going to use this long term, I don't have to plans to update further, so don't need latest updates.

Hope I'm not asking for anything illegal. If so, do let me know, I'll take this down