Ask your credit card company to increase your limit.
If you have a good credit rating they will increase it (so they can make more money from you!)
If they will not increase it.....don't try and borrow somewhere else.
HOWEVER
DEBT CARD (real name for Credit card) is one of the most expensive ways of borrowing to get into DEBT!
You would be paying about $100 INTEREST interest a month (PLUS your capital repayment!!!!) on minimum repayments. Get a Bank loan!
To be honest....... do you REALLY want to put yourself in BIG DEBT for a cruise!
The whole Western world is in DEEP trouble due to it's DEBTS, who knows what the future is going to bring, if you have any sort of problem in a few months time your "wriggle room" is greatly reduced if you have a BIG DEBT AT HIGH INTEREST RATES hanging over you!
Don't want to be a Jonah but think before you leap into debt!