The 1157 lamp is a 12.8 volt to 14 volt (12.8V to 14V) 2.10 amp (2.1A) / 0.59 Amp (0.59A) lamp with a clear S8 shape bulb and BA15D double contact bayonet base, with a rated average life of 1200 hours. This lamp is available under many brands and part numbers such as GE 26969 an 12294, Osram Sylvania 36531, Eiko 40194 and 40195, Bulbrite 752480, Satco S6957 and may others.  These lamps are sold individually, but are packed in boxes of 10 pcs. 
PRICE: $0.15