The cost of a microwave magnetron can vary depending on several factors, including the brand, model, and quality of the magnetron. However, microwave magnetrons typically range in price from around $20 to $100 USD. It's important to note that these are just rough estimates, and you may find magnetrons priced outside of this range. For the most accurate and up-to-date pricing information, I recommend checking with local appliance stores, online retailers, or contacting manufacturers directly.