I just bottle-fed a litter of 7 since they were 12 days old. They are now 7 weeks old today. I used this recipe solely until they were 3 weeks old and then started them on mash using the formula as the milk replacer, slowly weaning them off the formula onto just mash and then kibble. I swear by this recipe. It sustained my entire litter, and they are doing extremely well.
1 can whole evaporated milk (do not use "light")
1 can water
1 egg yolk--no whites
1 tsp Karo corn syrup
3-4 heaping tsp whole plain Greek yogurt
Mix well. I feed 1cc/ounce every 4 hours or so, and as they grow spaced the feedings to about every 6-7 hours as they were eating more with each feeding.
I like the Playtex nursing bottles, but make sure you use the newborn slow flow nipple as they can aspirate with a flow too fast. Good luck, and get your rest!