I always have a back-up, my little viking fills in when my Phaff has problems. I even have 2 Husky White Sergers. All my machines are service yearly, or before a big event. From Day one of purchase, my machines were serviced yearly, at the time I had ONE little Viking (1985 and in my 20's), while I was working on 5 Bridesmaid and 1 flower girl, low and behold we broke down. I had to borrow my moms' machine to finish, and I made a vow that one day I would always have a backup. I too live in a small town and the closest "repair" shop for machines is 90 or 246 miles away. After I was paid for the dresses, I bought my serger and wondered what the world was thinking about all those ruffles and not having one. Anyway.........If you can afford it, check out Ebay, second hand stores the classfieds and get yourself a backup. I have bought 2 new machines for daughters and 2 used sergers for self and a daughter, a nd have had no problems with ebay.
Good luck on getting your quilt done.