If you want to play the authentic experience, you can find it at:

Free-to-play mobile games like Gold Rush: Miner Simulator 3D on the Google Play Store use similar names but are entirely different games with ads and in-app purchases.

The game frequently goes on sale. You can track discounts on price comparison sites like AllKeyShop . System Requirements (PC)

Sites like Softonic host installers that eventually redirect you to the Steam store to purchase the game.