We do welcome inquiries on historic objects you have found, though as far as "appraisal" goes I can't say I've seen it pop up here before. Perhaps it may be time to add something in the rules about it.

What I can say as an old book afficionado: For selling/buying old books, the best place on the internet is typically AbeBooks. This particular edition has been posted by at least one seller. You may recognize the publisher, Harper & Brothers, from the now ubiquitous HarperCollins name. These brothers were James, John, Joseph, and Fletcher, and after a series of mergers would become HarperCollins. Singer and Symmons, as one may expect, were an academic and priest, respectively, best known for their scholarship on poetry and early English literature. Symmon's notes are lifted from an earlier compilation, as he had passed 10 years prior.

/r/BookCollecting