I could be completely wrong here- not a PRR expert, but at least in some photos, the window arrangement of the Kato Broadway's 5Dbr-lounge cars looks similar to the PRR plan 4131 "Falls" 6 DBR-Lounge cars. Easiest conversion might be to those PRR cars for use in another train.
Larry Goolsby's book on ACL lists one of the Falls cars operating on the Southwind (Chicago-Miami via PRR, L&N, ACL and FEC) in the 1960s, and it is certainly plausible one may have run on NY-Florida PRR-RFP-ACL trains as well (ACL had fluted 6 Dbr-Lounge cars, but many cars on those trains were pooled between the several roads). These multiroad trains are colorful and give you an excuse to run several interesting cars from various roads in the same train.
Unfortunately, all the other 5-lounge and 6-lounge cars in my resources are fluted- and tend to either resemble a fluted 4140 10-6 sleeper, or are fluted observations (the C&O cars).