ginger OEGB x golden sebright...
would explain the white legs, short tail, rose comb, patterned color...
edit: i just tried it on the chicken calculator (been on it for two days straight!)... RIR (ginger OEGB) crossed with golden sebright hen will give you "black patterned red incomplete halfspangled?"... so i might be right for the coloring... and the sebright genetics could prove it as well..
what other bantams do you have...? breed it with a golden duckwing hen OEGB and see what you get... if you get a BUNCH of different patterned birds like pencils, laced, birchen, half spangled, and gold colored off spring then you know there's sebright in there...