wow; just up my alley... i use these type of things for dripping and carto filling.
There's a place that sells these for RC model car fuel, 1/2 oz. The needle is built into the cap.
Also a wooden bottom feeder maker makes them for his "gravity feed" pv... 3ml bottle; snips the cap and fits a luer needle in.
these are the perfect thing, along with a Pyrex d/t for dripping.
I currently have about 6 or 7 with different juices at 1/2 oz and some 15ml bottles that fit the same cap/needle and a couple of the 3ml.
* I've found that some juice flavors will seep into the plastic and will not come out with washing... so you kind of got to dedicate the bottle to one juice.