Maorzo–How are your other tires? Sidewall cracks indicate deteriorating tires.
I can certainly understand the tight money situation, but don’t compromise on safety. My son has to watch his pennies. He blew a tire on his way to work about a week ago. He was able to get the car into a parking lot of a business. A friendly police officer saw it happen, gave my son a ride to the school where he teaches and then went back and explained to the business why the car was in their lot. At the end of the school day, my son put on the donut spare and drove to the independent tire shop where he trades. They didn’t have the right size in stock for his 1995 Ford Mustang, but did find a good used tire for him. He got away for $32.
Be certain that you have your best tires on the rear of your car. You can steer the front wheels, but you can’t steer the back wheels. A blowout or sudden loss of air on a rear tire is more difficult to control than a front tire.