Hey /sci/ what's your best obscure textbook source?

I'm trying to get a hold of the Instructor's Solution Manual for pic related (ISBN for the solution manual is 9780131471016) since one of the exercises in the main text holds a critical result for my research

So far I've tried having my advisor go through Pearson itself (even though there's a download link on the website you can find easily - it doesn't work with an instructors account because the book is out of print), as well as every legitimate potential textbook source, and the piracy sources in the /sci/ guide. Nothing so far.