U S A Valuable USA – 1903, 15¢ olive green (Scott 309), top plate number single – Estimate $1,500 MyNation May 20, 2020 1903, 15¢ olive green (Scott 309), top plate number single, o.g., never hinged, GEM quality example with perfectly balanced margins and breathtaking rich color; an amazing showpiece, Superb. Scott $475. Estimate $1,500 – 2,000