For those who want to have an alternative to Ranrans sleeves (especially those that cannot meet him), you could try those seleable plastic bags found at the grocery store. It is normally use as a container for putting food into the ref.
One brand that i could suggest is reynolds ziploc, but there are a lot of other brands. The plastic is air tight selable and is quite thick.
I got mine for 90-100 pesos for 20 pieces ( forgot the brand name) size is 7'' x 8''. But there are also those generic ones which is a lot cheaper.
btw, i bought mine at landmark.
just my 2 cents.