Tom,
I am experiencing the exact problem which is why I chose to purchase the CSX Legacy Boom Car. If all you're interested in is the "play value" by all means go ahead and purchase a Legacy Boom Car (road name not being important) just to be able to enjoy the sound associated with the crane. Check Ebay, there are still a few available with reasonable price tags. It seems that the PRR Boom Cars are as rare as Hen's teeth. Good luck in your quest.
Chief Bob (Retired)