I have some in stock. But you said your tank isn't fully cycled yet? Might be a better idea to scrub off what you can - take a bucket of saltwater, take out the rock, scrub off the bubble algae, give it a swirly in the bucket of saltwater, and then return the rock to the tank. That swirly will dislodge any detritus too and wash it off - that's partly what feeds the algae.
Once the tank is ready for livestock, then you can add an emerald or two, if you still wish to.
Jenn