I am not sure about Lionel part numbers. I have seen conflicting sheets , but this will be my wheel listing:
Chemically blackened w/ full nickel rim. Fits locos # 238E, 249E, 259E, 262E, 263E, 264E & 265E.
249E-19n Plain geared wheel, no hub, tapped 4:36 rod hole.
249E-20n Plain wheel w/ hub, tapped 4:36 rod hole
249E-21n geared wheel w/ hub, tapped 4:36 rod hole
249E-22n plain wheel, no hub, tapped 4:36
The set number will be: 249E-N
The same set w/ blackened rims will be # 249E-B
Both sets will retail for $40.00 a set.
I hope this is not too confusing. Harry