If you want to do this then why not. I’d go one of 2 ways.
- open it up and work out the size of the enclosure, half it and build 2 boxes with that size. Not sure how you would work out the port though so I would probably go with option 2
- remove the 2 tweeters and mount them in small boxes on your desk and leave the rest as it it (filling tweeter holes) under your desk.
Either way you will have speakers that play sound of some sort and If it doesn’t work as you hoped then at least you’ve had fun, and are a bit more experienced for your next go.
In my experience of building speakers from knowing nothing and just making speakers that look nice (no measurement at all) to actually using the speaker parameters to design proper enclosures and crossovers, they have all sounded ok. The later ones do sound better but my old ones didn’t sound bad.
If no one else offers any better advice, I say just give it a go and see how it turns out. 👍🏻
There are 2 x 3300uf 80v caps there. That tells me that it is a high voltage 70ish volts + & - power supply. There are probably other voltages there as well. Batteries are possible but not sensible. As others say a decent inverter or cheap car amp are probably a better option.