on 1867 $500 bond of the DUB-813-B-50, Dubuque & Sioux City Railroad Co. Image courtesy Eric Jackson Revenue Stamps. This is the only document on which the RN-T2 is found. Jackson reports six recorded. Below the T2 is a green 5¢ RN-P1. Although impossible to see on this reduced image, both revenues are printed over a 50¢ orange RN-V4.