This is the same price they used to list them for on their eBay account. I bought 2 at $29.99 months back, and I can vouch that they work well and are in decent shape. Mine had minor scratches on the edges and such, but nothing that visible.
Keep in mind that this only comes with the one ear bud that comes on the headset, not the full set of sizes. I don't see that specified on their site aside from just saying "ear bud" on what it includes, but it was on their listings. If you want other sizes, you can get a full set on eBay for $3 or so.