A bit tricky to obtain unless you're diabetic but I used a small 1ml syringe with a hypodermic needle, somewhere around a 25 gauge tip. You need a prescription however. My local clinic said they don't have any so try a pharmacy, the pharmacy clerk was verrrry reluctant to give me one, this was back when I needed one to inject earthworks with air so they'd float for trout fishing. She originally said no, but as I walked away she whispered me back and just gave me one with a wink ;)
For vinegar and muriatic acid the small tips work really well but if you're using aptasia x you may need a larger tip as there's some sediment that will clog the tip before you have a change to get any liquid out

So either be kind and explain to your local pharmacist what you need one for (cross your fingers), or try eBay

They should just sell them, its not illegal. Theres a medical supply store by bcit that sells needles with no explanation needed. Also one in maple ridge.

Don't they just give out free needles downtown Vancouver? Or do you need heroin to get them.

Lol.

The safe injection sites in Vancouver do not allow you to take the needles with you. You get a sealed syringe, a fresh needle, go into a private booth and chase the dragon. It`s all closely monitored with a nurse on site.

Don't ask how I know this, lol.

You're family doctor should be able to give you a fresh needle if you explain the situation to him.

Any medical supply company or drug store should sell you the gear. I bought a box of syringes and a box of needles, enough to last forever, unless I take up some new habits!