2.75 x 4.75 card sleeves Pro Safe Perfect Fit 35pt–75pt Magnetic Holders 100ct Free Shipping *10% more sleeves than the other guys S 75 & 100 Soft

Pheromosa can be obtained from Deluxe Pack: ex pack in the Deluxe Pack: ex set

However, if you want a guideline for what kind of cards to look out for, it's good to refer to the Limited archetypes available

While Dark Magician Girl the Magician's Apprentices core stats are hardly awe-inspiring, collectors love her (I wonder why?) so her Quarter Century Secret Rare from Alliance Insight is fetching up to $170 right now at TCGPlayer and other secondary markets like eBay

Modern 9-pocket binders have a material backing that separates the front and backside of the page, so the cards don't rub against one another

Finally we have another staple of Legacy enchantress decks