You shouldn't be surprised your egg production is hurting. Rice is a very nutritionally poor feed. It low protein, low Ca, low, low minerals and vitamins. The only thing it really offers is lots of carbohydrates and calories. If there were off their feed for 6 days, I would expect they would need another 6 days to get back up to normal.
Living where you are, I would have a backup plan in case this happens again. First off exhaust any other foul feed options. Non medicated starter, grower, all flock or meat bird with Ca on the side is the best alternative. Next what whole grains do you have available? You must have locally produced field corn with the cattle industry. Corn, soybeans, oats, wheat berries, barley, field peas, lentils or sunflower seeds are all better more nutritious options than rice. Cutting the layer with one or a mixture of these would buy you some time. Even cut it with the rice if you have to but don't give them the rice by itself. They will pick out the whole grains first but they will go back and eat the layer.
If you don't have any of that available, I'd look at other livestock feeds, Rabbit looks like a viable alternative short term. Everything in it is good for chickens (alfalfa, soy, grains). Protein levels are ideal. Ca will be deficient. The one problem will be the slightly higher Na content (will be true with any livestock feed you substitute) but for a week, I'd rather have the added nutrients of a formulated feed. Goat feed would be my next choice. Lastly, if you have to, use a horse feed. I'd stay away from the pelleted feed just because of the size of the pellet (usually 3/8" where the rabbit is 3/16"). The cheap horse feeds are a blend of whole grains (corn, oats and barley), some type of vitamin/mineral pellet and a ton of molasses. Again, not the best alternative but you're talking a week.
Chickens can and will eat a bunch of different foods if they have to. What do you have available to you? You can add fish (protein and Ca from the bones), fresh fruits and vegetables (added vitamins) alfalfa (protein, carotenes and Ca) dried catfood (protein) stale bread... just add something more to the rice.