Questions about Old English Game Bantams

[DavidKerk]

I am planning on buying some Old English Game Bantams from Family, Farm, and Home. They are sold in the "assorted bantams" section. I believe the only other breed in the bin is the Sebright. How do I distinguish the two from each other? Is the eye-liner-like marking good enoung to tell them apart? Also, they are strait run. I know there is really no way of knowing what gender they are to an untrained person but is there any way I can be about one percent more sure that mine is hen or is it impossible?