Not as easy to search for as one might think, I only found the one above with a slimmer one, I have one in a 120ml bottle that I have kept after I used the juice.
Yeah there's a lot of bottles but very few with the tapered end, unless like you suggested I reuse bottles which is not what i want to do really, as I am mixing my own juices. But hay ho it looks like that's what I'm gonna have to do.