 However, VR reassessed its motive power requirements and opted to sell ten of its brand-new, second generation N class locomotives to the South Australian Railways, and increased the J class order to sixty locomotives.At the time of order, the per-unit cost of the locomotives was £36,000 ($72,000) each.With fluctuating oil prices and an unreliable supply of coal in the early 1950s, the VR appeared to take something of a bet either way, ordering thirty of the class as coal burners and thirty as oil burners.