Selenium find all elements by xpath
To grab all prices on that page you should use such XPATH:
Header = driver.find_elements_by_xpath("//span[contains(concat(' ', normalize-space(@class), ' '), 'price-amount')]")which means: find all span elements with class=price-amount, why so complex - see here
But more simply to find the same elements is by CSS locator:
.price-amount