+1 on Ken's marinade injector thought. I use one to refill the many small containers I've stockpiled over the years. I especially like mini sized actual toothpaste, sunscreen, anti-fungal cream tubes because then there is no question about the labeling.
I saved all the micro toothpaste tubes I got in Chinese hotels. And I get a lot of medical, professional samples of OTC and RX drugs. It helps to have an MD wife, but you can ask any doc for stuff within their speciality. Drug reps inundate them with little samples of everything new and wonderful.