The easiest place would be amazon or a online air gun shop.
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The Webley Mark III is a rifle not a gun and has not been in production since 1975. You could try a gun shop or online Firearms dealer. Several firearm dealers sell used air guns & rifles.
What do you mean by "atrigger". If you are looking for the Owners Manual for the Crosman Mark 1 Pellet gun, then see the link below.
Try Numrich gun parts
Try the Blue book of gun values for a general ball park figure
If the gun is complete and functional, $300.00 to $800.00 depending on the condition.
The value of the Webley Mark 2 revolver with a serial number of 43383 varies with the condition of the pistol. This gun sells for about 450 dollars to about 1000 dollars depending on the condition.
The gun was an ivory-handled .44 Webley British Bulldog revolver.
Please state the condition of the pistol to get an estimate of value.
Depends on where you live but usually you have to be 18 to purchase one
It can leave everything from a welt to penetrating the skin and doing physical damage. Always treat a pellet gun like a firearm.
You start by reading reviews. I suggest going to online reviews that people have written about the various guns they have purchased. You also need to select the type of airgun you want to purchase. Air you looking for a pellet gun or an air-soft pellet gun? How much can you afford? All these things will help you determine what you can purchase. Pellet guns cost as little as $20 and as much as $3,000 so do some homework and make a selection.
In the Unites States you have to be 18 to purchase a pellet or BB gun, but you can be any age to shoot it under adult supervision.
It depends on the model and the caliber of the Pellet gun.