I need help with a chevy 4 wheel drive selector switch?

2003 Chevy 2500HD 8.1. i believe the switch is bad and needs replaced. however, every replacement switch that i can find is a 4 button. i have looked at wrecking yards and every auto parts store i can think of. can anyone tell me why my truck is the only one i can find that doesnt have the auto 4wd option? i checked at the dealer and they do have the switch i need but i hesitate to pay 340.00 dollars if there is a cheaper option.|||you could also try LMC truck parts....the most common is the 4 button switch, but if the dealer has it, then someone will have it cheaper aftermarket for sure|||Try these guys.www.am-autoparts.com|||go to www.lmctruck.com