Who has the cheapest price on stair / bull nosing? I'll be using it with a Bruce 3/8" engineered plank. I searched some places on the net and they want +$50.00 for a 6' piece. At that rate it'd cost me $300.00 just for the bull nosing alone

Prefinished moldings are high dollar sorry to say there is not much you can do about it. You may get lucky at a salvage type store.