I've never had to use parcel forwarding or proxy services for Korean beauty products, so the following links are all for stores I've personally purchased from.
ebay
Pros: Good old ebay! One can find just about anything here.
Cons: It's also a minefield; you'd need to do your research and make sure that the seller has good feedback, because there are plenty of fakes floating around.
BeautyNetKorea
Pros: Free shipping on everything, orders are processed quickly. My orders are usually shipped the next business day.
Cons: Bloaty website with far too much going on, difficult to navigate, doesn't have a large range of products from each brand.
Gmarket
Pros: Has just about everything you can think of, cheap prices, fast shipping via EMS.
Cons: Confusing to navigate, the sellers use images so I can't Google Translate product ingredients, and any overpaid shipping will remain in your account as credit rather than refunded back to your payment card. Honestly, there are better options these days.
Jolse
Pros: Free worldwide shipping. Frequent 10%-15% off sales. Incredibly generous with gifts!
Cons: Doesn't have the cheapest prices for everything. As always, compare prices before you shop.
Koreadepart
Pros: Great prices, huge selection of brands and products
Cons: The site's search function is terrible, difficult to navigate. Takes around a week to ship and the shipping itself seems very slow. My biggest gripe with this site though, is how you can't select or copy any of the text. This means if I wanted to google a product, I'd have to type out its full name. Really inconvenient.
TesterKorea
Pros: Cheap prices, frequent sales/discounts, HUGE range of products. You can even request for products to be added to the website through their forums.
Cons: Have to pay for shipping. Orders typically take at least a week to process. I've actually had some orders in processing status for 2-3 weeks.
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