Consider subscribing to the podcast. Subscriptions often provide ad-free listening, exclusive content, and support for the creators.
If you don't want to buy everything, buy the best one. Ghosts of the Ostfront (WWII Eastern Front) is widely considered the greatest podcast series ever made. Buy that single series for $5.99. If it changes your life, buy the rest.
The torrent community, in this specific niche, often operates with a code of ethics. If you read the comments on torrent sites or Reddit threads sharing Hardcore History files, the sentiment is rarely malicious. Instead, you find recommendations like: "I downloaded this to see if I liked it. I ended up buying the full series from his site to support Dan."