Hylian Shield

Castle Town's bazaar is the counter: 80 rupees. Speak with the guard at the Death Mountain gate first and the same shop can roll a discount somewhere from 45 to 75. I am not telling you which number you will see. The free copy is a grave in Kakariko's yard at night. The slingshot is a Deku Tree dungeon item, so rupees are not needed to buy it.

Like Likes can swallow the Hylian Shield and equipped tunics; defeat the creature promptly to recover them, which is the practical reason to own it before the adult temples. The Mirror Shield from the Spirit Temple is a separate shield, and it is an adult item with a job, reflecting light, not a strict better-of-the-same. Child Link can own the Hylian Shield and still look wrong using it, because the game parks it on his back. Buy or dig accordingly.

Child Link crouches beneath the shield rather than raising it as a forward-facing arm shield. That makes it useful against falling hazards but changes how the player should approach a melee enemy. Adult Link can carry it normally and keep the sword ready. Metal fire resistance does not mean protection from every attack: positioning and the direction Link faces still matter. A Like Like is another exception because it can swallow the shield and tunic rather than dealing a simple blocked hit. Defeat it quickly and retrieve the dropped equipment. In the Spirit Temple, equip the Mirror Shield for light puzzles; the Hylian Shield cannot reflect those beams into sun switches.