IMO, it means that its cost is just under a trillion dollars (say, a trillion minus 1 dollar). "Eyelash" is used to express this short distance between the cost and a trillion (Trillion - Wikipedia, the free encyclopedia). There are other such expressions for "short distance", but we'll have to wait for native speakers to provide them.
PS: I believe you could also say "a hair short of a trillion", but I'm not sure if I'm translating directly from Spanish here.
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