Red Seal
noun
A vermilion colored seal is a red seal. Just look up the (Japanese) word in Google Image search and you'll see what this is.
しゅいん
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
この紙に御朱印を押してもらえますか？
Could I get the red seal of the shogun on this paper?