Joe,
This 3 L stein was made by Mathias Girmscheid circa 1960. Not highly collectible, but you got it for a decent price if it is in mint condition. Does it have the initials “KB” on it. The stein was designed by Karl Beuler. The relief pottery steins were targeted to the souvenir trade. Etched, character and reservist steins are more sought after by collectors.
Are you a member of SCI yet? If not, you should join and find out if there is a local chapter near you. Knowing other members and talking with them will help you develop a strategy for adding to your collection. There are a lot of steins out there and the more information you have, the better your collection will become.
Ron