I was going to suggest Cibie Oscar spot beams, but they may not meet your "less expensive than Rallye 4000" requirement. You could always pick up a pair of PAR46 housings such as
these or
these (same picture on both pages, but the actual housings are chrome vs. silver paint; the black equivalent is Truck-Lite number 657H).
Then put in whatever 5¾" light unit you want. A GE H7680HIR sealed beam is an 80w unit that produces a 300,000-candela, 6½° spot. No width, no fill, nothing but
distance. Aim is obviously crucial.