But then you will have to sacrifice your boat, unless you have more gold lying around.
Step 1: Buy a 10-foot ladder.
Step 2: Cut rungs off of ladder, resulting in two 10-foot poles.
Step 3: Sell poles back.
Step 4: Buy more ladders.
Step 5: Repeat steps 1-4 until you can buy your boat.
Or you could try to have your team's Druid Animal Empathy a whale.