First, if your credit is as good as you say, you should be able to command an attractive rate from the dealer, your bank or credit union. Let them compete for your business, too - you may be surprised.
Have you considered a home equity line of credit? Rates should be lower than rates for a used car and also the interest may be tax deductible.
It would take time for you to close on a home equity line of credit, but if you're not in a hurry, I would consider it based on your home equity balance.