Welcome to Gaia! ::

It looks quite good, and I find it interesting that you're going for that style. I think the eye on the right is too far from the edge of the head, plus it looks like it might have a different size than the other eye. If you move it closer to the edge, you might also want to make the eyes wider. I know Link's eyes and eyebrows show through his hair, so you might want to do the same. I'm not 100% sure if that's the eyebrow showing through the headband or if that's just another fold/stretch line on it... but, in any case, I think both eyebrows should be showing through it.
Here's a picture of the Wind Waker Link that I just Googled: http://zs.ffshrine.org/album/wind-waker/art/zww-link5.jpg
I suppose the mouth could also be more like that.

I've got no clue since I don't really hang around Gaia much, haha. I don't even know what you'd consider "a bit". Back in my day I'd sell things for a few thousand gold, but you can't really buy anything with that, especially with how we have evolving items and stuff today... Monthly collectibles would be around 15k upon release back then, but now they're closer to 50k or even higher. Uh... anyhow, didn't mean to go too off topic there. The Zelda series and Smash Bros are rather popular, so fans would probably want one. Again, I have no idea what avi art prices are like or how much you'd be looking for, though.