Are these federal or private loans from your undergrad? Federal loans can be placed on an income driven payment plan that will keep your payment affordable even if it takes you a few months to find steady employment. Even if they are private, you may still have some options for delaying or reducing your payments, you will just have to contact the lender and explain the situation.
You should never trade debt like this for a higher interest rate. A much better (but far from ideal) solution would be to refuse most of your loans, but accept $1000 or whatever 2-3 months of payments on the undergrad loan would be. That way, you can have that money on hand to cover the payments after you graduate. A far better plan is to return all of the money (since you don't need it for your education expenses), and use the time you have to make a plan to be able to pay your loans when you graduate. Can you pick up a part-time job, or some side gigs to save enough money? You should be planning to have a financial cushion for the transition anyway, and this is an important part of that.
