Hey Jim, that's a real, genuine American Crocodile! I've never seen or heard about these L-5 locos before. Truly amazing!
Obviously they were developed shortly after our Swiss crocdiles had great success on the Swiss Gotthard mountain line in 1921.
However, if you look at the driving wheel diameter, the PRR engines were built for speed. Jim reports a speed of 70 mph for the L-5, while the Swiss crocodiles were built for a top speed of only 40 mph - but they pulled like mad on the steep Gotthard ramp (2.8%). They developed about 2400 hp and after a rebuild in the 50's even 3650 hp.
Charlie is right - a kitbash should be possible. You 'only' need two Atlantics (4-4-2) for the wheels...
Ron
PS: What are these funny, tiny pantographs for? Were they really used for regular mainline running?
A remark to my pic: Look at the smaller wheels of this Swiss crocodile - compare with the size of the respective cabs! And note the strange layout of the driving rods!