I'm 99.9% certain that every episode still exists in full, which would mean this segment still exists. I recall reading a number of times long ago that Sesame Workshop has restored/remastered EVERY single episode a number of times over the years, even before Noggin started (and therefore when it looked like older episodes would never be released or rebroadcast again).
When that line in the book about hoping that at least a still exists somewhere, I think he was referring to a picture from the event where Jon Stone was hit in the face with a pie.
A few years ago Sesame Workshop allowed fans to nominate clips for 40 Years of Sunny Days. If Sesame Workshop ever provides the fans to nominate clips for another DVD release (maybe for the 45th or 50th anniversaries) I'll have to remember to nominate this "Surprise" song.
There's a number of clips that were considered holy grails but in the last few years have been uploaded at sesamestreet.org and/or released on DVD. Some such clips include:
- Baker #1 - now at sesamestreet.org and on the 40 Years of Sunny Days DVD
- There's a Hole in the Bucket - now at sesamestreet.org
- Beat the Time: Grover - now on the Old School Volume 2 and Best of Sesame Street Spoofs! DVDs and at sesamestreet.org
- The original "People in Your Neighborhood" - now on the Elmo's World: People in Your Neighborhood DVD
- Seven Monsters (a rarely-seen animated cartoon by Jim Henson and Maurice Sendak) - has surfaced on YouTube
- Any clips with Aristotle - two of them are now on sesamestreet.org, while one of those clips is on the Old School Volume 3 DVD
- Anything with Shivers the Penguin - Copper Pot Pictures recently uploaded a clip of the character on YouTube as part of it's "I Am Big Bird" fundraising campaign
- Richard Hunt's performances as Elmo - a couple of clips appeared in the Being Elmo documentary
- Telly Monster in his original TV-obsessed form - A clip of his first scene appears on the 40 Years of Sunny Days DVD, while his entire debut episode is on iTunes
And there are clips that I believe are still considered "holy grails", though some have surfaced in other languages. These include:
- The original Rubber Duckie (a clip showed up in The Muppets: A Celebration of 30 Years, but Sesame Workshop seems to think that the second and most well-known version is from the first season)
- "Crack Monster" cartoon (not a monster who likes crack, but a crack in the wall that forms the shape of a monster)
- Anything with Leslie Mostly or Deena and Pearl
- The Count being served by waiter Grover
- The Count's appearance on Miami Mice
- Lucy in the Sky with Diamonds (I think that insert only aired once)
There's also the rarely-seen specials "Out to Lunch" (The Jim Henson Legacy occasionally shows clips at screenings), "Sesame Street at Night?", and "The Jean Marsh Cartoon Special", though "Out to Lunch" seems to be the one fans want to see in full the most. And because of the recent "I Am Big Bird" campaign I've heard of a 1984 special I had never heard of until then, "Big Bird in Austrailia". A couple of clips from that (including the aforementioned Shivers the Penguin clip) were posted on YouTube.
I don't know if others would consider these to be "holy grails", but I'd really like to see any Buddy and Jim, Larry and Phyllis, and Wally and Ralph segment that hadn't been shown on Noggin or iTunes. It seems Sesame Workshop only wants to release those to the public when they release episodes that featured those segments. Ditto for any of the claymation letter segments Jim Henson worked on in the first season (three of them -- the letters S, Q, and U -- have aired on Noggin).
I'd also like to see more of Michael Earl's performances as Forgetful Jones and Snuffy (only one of each has surfaced), and some of Brian Meehl's performances as Elmo.
As epic as this segment sounds, I'd say that a truly episode segment (which most likely doesn't exist) would have to have had the ENTIRE cast. All adults who were on the show at the time and all Muppets who were being used at the time (maybe even characters who were no longer in new material but whose old segments were still being broadcast in new episodes).