Enamels, and later, acrylic enamels replaced lacquers as standard automotive finishes from the 60's into the 80's. If properly prep'ed, applied, and cared for, an enamel paint job will last a long time. And, yes, there's clear enamel, to get that "depth" on a metallic base. It's tougher than lacquer, but takes longer to dry/harden. Acrylic lacquer is still favored by custom painters because it dries fast, subsequent coats bond readily, and it buffs out to a mirror finish.
$350/gal is way high for acrylic enamel...sounds more like the price of urethane, the base coat-clear coat system so common nowadays. Urethanes tend to be the best available, and even come in a water-borne formulation to reduce toxic emissions. Fast curing, extremely durable, and highly buffable (is that a word?), just super expensive.
Any paint job is only as good as the prep work. I've got an old motorcycle with a 25-year old acrylic lacquer paint job: red metallic under a few coats of clear. A couple scratches and chips around the edges, but it still polishes up nice.
I'd say shop around. You generally get what you pay for, but it's good to know what you're getting.
Good luck.
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