If you have found this then you probably know that when Harpo passed away he left his harp to the State of Israel. After much research I found that the last location it was at is the Jerusalem Academy of Music and Dance https://www.jamd.ac.il/en
This summer (2015)when I went to Israel I decide I was going to see Harpo's Harp. I did email the JAMD with no response. So with my brother-in-law Udi we went to find Harpo's harp. After wandering around the Campus and asking where the harps are kept, we ended up in a practice room (I think it was room #511 or 513). There were 3 harps one of which was Harpo's, we took some pics, played it and put the cover back on; mission accomplished.