In reality it's probably only suitable for a static display. While Wikipedia claims 'Most original JetStars have been retired, but many 731 JetStars and JetStar IIs are still flying in various roles, mainly as corporate and private jets.' Poking around on line I found this article on
AVWeb from December 19 stating that 'Retirement came this week for what is believed to be the last flying Lockheed JetStar.' The original engines don't meet modern noise regulations, You can't just throw different engines in. The need to be correct and approved, an STC (Supplemental Type Certificate in General Aviation terms), I'm sure there's something similar for JetStars, but are 'correct' engines available? Other than for an uber fan who wants it flying just because it's Elvis's plane.