The best place to get an answer to your question is "Daisy." They offer a free service to tell you more about your old Daisy. The reason I am not answering this question is:
You have not given any description of the current condition this rifle is in. Without more information, I can not give an estimate of value. See the link below.
The model 1938B came out in 1979
1979
it was made in 1979
The 1938B model shoots at 220 Feet Per Second.
The lot number is usually on the right side of the barrel.
It's usually on the top right behind the sights. It will say 1938B or something like that.
Oh, dude, a Daisy Red Ryder 1938B BB gun in its original box in excellent condition can fetch around $200 to $400, depending on the market and demand. But hey, who needs a BB gun when you can just tell jokes and make people laugh, right? Like, priorities, man.
Daisy has made about 5 different Versions of the 1938B BB rifle over the years. If you want mode information I suggest you contact Daisy. Daisy offers a FREE service to tell you more about you old Daisy. See the link below.
Made in 1979. In excellent condition it would be worth around $35
Daisy offers a free service to tell you more about your old Daisy. See the link below
New in box it would be worth around $85
This is the Diamond 60th edition. It would be worth between $40-$50 in good condition