Ordered 50 NTAG203 stickers on Wed just before midnight, arrived on Friday. The tags work find with my cheap RFID-RC522 reader using the Arduino RFID library, max read range is probably 3cm with that reader. Some MIFARE S50 tags seem to have a better range than that but they cost more and I couldn't find stickers anyway. If you want to 'Id Tag' documents these are a simple and cheap way to do that. Note the tag Ids all seem pretty consecutive within the batch I received, so if memory is very short your might be able to throw away some common bytes and still keeps Ids 'unique' within your batch.