You wont be able to make that comparison at all.
Ok, nowdays you can pick up a transcontinental flight for $1000 and 14 Hours.
In 1850 a customer had a six week journey from northern France, let alone the USA. Even if you drag your pricing right the way forward to a customer jumping on board the Titanic, the costs of the journey were literally incomparable.
The capacity to export goods to avoid tax is basically impossible to take into account. Hell, even inflation in...