Indium can be purchased from various suppliers, including chemical suppliers and metal traders. Some popular online retailers that sell indium are Sigma-Aldrich, American Elements, Alfa Aesar and Atomeon.
You can also try searching for local metal suppliers or industrial supplies companies in your area. However, it is important to note that indium is a regulated material and may require special handling and documentation for shipping and handling.
It is therefore important to ensure that you comply with all necessary regulations and safety guidelines when purchasing and using indium. The most important step here is to buy this from a company that works with regular suppliers. This way you can be sure that your goods have been tested and that the quality is consistent. The company takes care in the background that all formalities are handled and that the goods have been imported for free circulation. Here, of course, the company's responsibility plays a major role in ensuring that you are always well looked after. Or do you know, if you buy it from a marketplace, whether you might not have simply been delivered tin?