You can probably move that drive with 50% remaining into an external case, and then access it from your new computer or any other computer for that matter.
Doesn’t Apple take back their old computers? Perhaps they only do so when you buy a new one. My city has local computer recycling and refurbishing companies, any of which might be interested in your 2011 MBP. Alternatively, you could place a Craigslist ad offering the old hardware. No sense tossing those electronics in the trash, even though fixing it yourself might be way more than you want to get in to.
By the way, sometimes it’s not the whole logic board that fails, but perhaps one of the smaller boards. My very old MBP was dropped, damaging the charging input, which means that I was one charge away from permanent death, since there’s no way to run off battery or mains power if the connector doesn’t work. This turned out to be a small board with power, USB, headphones, and microphone. I found it new, online, for $60, and it was easy to replace. Of course, you may have already confirmed that your entire logic board is bad, but I just wanted to point out that there are other failures that can take out the whole laptop, even with a perfectly good logic board.
