Gasses for household applications (propane, butane etc.) often come in small disposable containers, such as metal bottles or cans. I know that it is possible to refill some of them, such as one-pound bottle that is ubiquitous in North America, but there are some safety and legal issues associated with that (latter, however, is to prevent people to commercially refill those in potentially unsafe conditions and/or sell them as new, as I understand).
Are there dedicated small multi-use containers for various gasses either in metric or imperial sizes with simplified refilling infrastructure? Out of non-traditional products I had only seen Ragasco and Lite Cylinder, which offer composite LPG tanks, that are lighter and supposedly safer than regular steel ones, offering several other advantages, such as ability to clearly see the level of fuel, and non-corrosiveness (boon for marine applications). But they do not offer any small-size products (minimum is 5kg propane containers or thereabouts).