Sheridan made their first air rifle model in March 1947 so I don't believe yours could be from the 1930, more likely it was made sometime after 1972. The Sheridan model is a 20 caliber rifle not a .177 or .22 caliber like it's cousin the Benjamin model 392.
The current Sheridan Blue Streak, CB9, sells for $190 at present.
In order to give you an estimate of value I need to know the current condition of the rifle. Is it still working and holding air? Is it in Poor, Fair, Good, Very good, or Excellent condition? without more information it is not possible to give you an estimate of value.
Sheridan C silver streak in good condition would be worth between $125 -$160 USD
The Sheridan Silver Streak is a 20 cal pump air rifle. To get an estimate of value please state the condition of the air rifle. Is it working? Is it in poor, fair, good, very good, or excellent condition.
This is for the Sliver Streak not the C9 silver streak. In good condition it is worth between $85- $105
If it is a "C9 silver Streak" it would be worth around $140. If it is a "C Silver Streak" it would be worth around $235
I assume that you are asking about the .20 cal Sheridan C Silver Streak NOT the C9 Silver streak. (It's worth more.) New in box: Excellent condition $185 Very Good $160 Good $120 This is just an estimate.
What condition is it in..
This is possibly the most frustrating airguns to nail down as to the exact model. First of all let me explain. Sheridan was a standalone company. In 1977 Benjamin purchased Sheridan. Some guns were called Benjamin/Sheridan, in 1992 Crosman purchased Benjamin and Sheridan. They decided to call the .177 and .22 caliber rifles "Benjamin" and the .20 caliber rifle "Sheridan." But for awhile they were called "Benjamin/Sheridan." So now we have the models C, C9, CB9, C9PB, Along with Blue Streak and Silver Streak. Not to be confused with the Crosman/Benjamin "Super Streak." (Confused enough) Okay here is what I think your value is according to the Bluebook of airguns 9th edition. in very good condition it is worth between $105 to $135
Depending on which version of the Silver Streak, the C Series or the C9 Series the value is about the same. In Very Good condition it is worth around $135 to $155 If it has no wear, scratches, dings, rust, pitting or other damage.
It would be worth between $65 - $80
It's worth around $130 IN WORKING Condition. Also check the ( link below ) for shops that repair older air guns. Today Crosman air gun company owns the Sheridan name and products.
You did not state the condition of the rifle, so I am going to assume it is in "Good" condition, Not Very Good or fair condition. It would be worth between $85 - $105 add 15% for the Box and Owners Manual. If the rifle is in "Very Good" condition then it would be worth around $130
There are many versions of the C series Sheridan Let me explain: Sheridan made air rifles started in 1945 and made a few variations of the C series. Benjamin bought out Sheridan and continued to make the C series ( C9, CB, CBW CW ) From 1949 to 1990 it was marked Sheridan. In 1972 serial numbers were redone and started with #000000. Crosman bought out Benjamin (1992) and continued to make the C series Rifle (It's very popular) The rifle was made in .177, .20, .22 caliber. From 1998-2000 Crosman marketed the C series .177 and .22 Caliber as a Benjamin and the .20 Caliber as a Sheridan. I believe your rifle was made sometime after 1972 when the company was still owned by Benjamin. You may see a C9 Silver Streak or a C9 Blue streak. They are the current C series rifles Final note: at one point during the 1950's the rifle was marketed as a Benjamin Franklin as a marketing ploy. Benjamin Franklin had nothing to do with it. But his name got stuck on it anyway. Along the way the rifle has also been marketed as a Benjamin / Sheridan. ( You confused? so am I.) A rifle like this in good condition would be worth around $105 + or - $20