According to Edith Reiter's 2014 book this instrument was completed on 10 September 1957 and originally sold to a buyer in Canada.
Howe & Hurd (2004) describe heckelphone #4963 as a model 36 voll cons (one of the earliest of this type) with silver-plated keys and an additional muting bell.
As of 2020, heckelphone #4963 is located in Bellingham (WA), USA, owned by noted heckelphone specialist, Peter Hurd. Previously, it belonged to bassoonist Cornelia Biggers of St. Petersburg (FL), M. Simpson and wind instrument repairman Dennis Adcock of Edmonton (AB), Canada, who offered it for sale in 1997, at which point it had purportedly only been used a few times since it was built and mostly been maintained in controlled-humidity storage.
This heckelphone is reported to have been used in the Edmonton and Calgary Symphony Orchestras.
Further details of the history of heckelphone #4963 remain unclear.