It's not a 54. From what I can tell, I would think a 1951 300. series. 51 was the first year of the vent glass in the door.It looks like the door handle is the lever type which 51 was the last year. 52 and 53 used a push button. 54 had a 1 piece windshield.
Of course, someone could have put a 51 door on a 48 because they fit.
