Oh my goodness! I was there for this as well in July 1984! It was my 6th birthday on the day I saw this parade. To this day one of my fondest memories is thinking that Donald and I shared a birthday! I have many of these same photos and I vividly remember this parade and this song like it was yesterday!! So happy to see this footage!
They also made a TV program about Donald's 50th in the States, which I myself have on tape at home. It is hosted by Dick Van Dyke, who is certainly no stranger to Disney himself, having appeared in several movies, including the classic "Mary Poppins".
They played this song as one of the selections at the character breakfast at Walt Disney World's Contemporary Resort Chef Mickey. I was hoping to find a good copy too.