This may help get you some stopping power. Figure out which brake lines are leaking. Then look at your master cylinder for your brakes and figure out which brake lines off of the master cylinder supply those brakes. Take off those lines and plug the master cylinder holes with a nail and then screw the nut back on the master cylinder. This should help restore braking power to the brake lines that are not leaking. You won't have full stopping power but some is better than none. I drove a car using this technique from Ohio to Tennessee this way.