To be perfectly honest, Lincoln's funeral was the first great memorabilia event in American history. If you dig into it, you'll find a lot of things produced specifically to market to the surge in feeling among Americans. Lincoln's assassination, capping the end of the war, was a titanic event, and everyone knew it at the time.

Sheet music like this was one thing. There were buttons and bunting as well. Dried flowers from funeral processions were particularly popular, stored in scrapbooks.

If this is part of a family collection, I'd value it for that. I'm not an expert on this particular piece and can't give you an estimate on its value, but I can say that this type of thing was produced widely.

Here's another song in the collection written for lt. Elmer Ellsworth civil war music

Lincoln Library in Springfield seems to have a few copies of this in their catalog, so I'm not thinking it's too rare. You can give them a call and ask them if they have any additional information about the piece, but keep in mind archivists are generally prohibited from giving out appraisals. But /u/The_Alaskan is absolutely right, lots of death-themed Lincolnalia rolling around ebay, your item is perhaps just interesting for being the 19th century equivalent of this sort of thing. :)