I don't know how much trouble the author went through to get those symbols, but he has got ♭, ♮ and ♯.
Questions written like this do look a little better, and I would not be surprised if there were other musical symbols in the character set that would fit nicely.
Lets at least place a sentence in the Ask Question and Edit Question pages so that a user can simply select and drag or copy/paste one of these symbols into view.
A small line of text anywhere on the page
You may select and drag any of these symbols into your question: (♭ ♮ ♯ ♪ ♫ ♩)
Possibly in the right hand sidebar, but make sure you update Edit as well as Ask. Perhaps just a line under the textarea.
If you want to save space, you could just place an undocumented
♭ ♮ ♯ ♪ ♫ ♩ anywhere on the page.
To take it a step further, they could be editor buttons, but that is not necessary.