Mmmm what if you do want to go and visit your sister?? Can you get there by bus etc easily? What about Dr's/Child Health Nurse appointments etc? How will you get home from hospital? If you are able to do most things already without a car more power to you! I wish I could do 231kms in 9 weeks! Far out, we do that in less than a week and with the cost of petrol I wish we didn't.
Maybe you could check out places like Hire for Baby that are close to you so that if you did need one in a hurry you have their phone number handy and can get there to pick one up. Good luck.