I think this shows one of the downsides of trade barriers very well: You get stuck with undesirable industries (diesel bus manufacturing), binding capital and labor better used elsewhere (and you easily end up with underperforming, overpriced solutions, too).
But I'm curious how much this actually affects transport costs. If such a bus is used 12h/day, then even overpaying 100% for the vehicle should get outscaled by labor + maintenance pretty quickly, long before the vehicle is replaced...
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