Another way of looking at it. the fridge uses 35 amp-hours every 24 hours. That's 35 x 5 = 175 amp-hours in 5 days. Your batteries can provide 133 amp-hours, as I said. That leaves 175 - 133 = 42 amp-hours to be provided by other sources. A small solar panel should be able to give 42 amp-hours over the 5-day period. A 100 watt panel will do this even if the weather is a bit cloudy.