I'm afraid that one requires some calculation. First, figure out how many movement points it's going to take to get there. It helps to turn on ship movement lines in the F2->Options menu for this. Assuming you have movement lines turned on and the ship selected, count the squares from the destination to the last square with a lower number in it, add that lower number times the ship's movement per turn, and add the ship's current remaining movement points for this turn. For a ship with 5 movement per turn, none left, and the following movement line in the final system:
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-------766666
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The movement points required to get there would be 3 + (6 * 5) + 0 = 33. Multiply this number by 10 times the number of engines on the ship. The result is the required amount of supplies for the trip.
A ship with full supplies and no supply storage from anything but the engines can move 50 squares before running out of supplies.
To find ships that are low on supplies, browse the ships list (F6) and look for a barrel with a yellow or red bottom under the name. Yellow indicated less than 1000 supplies, red means no supplies.