You cant'.
Since they are not registered, there is no way to answer your question. In the US, MOST guns are not registered- there is no law requiring that guns be registered. It is a popular misconception that there IS such a requirement, but there is none on a Federal level.
Many places don't require it.
Despite belief to the contrary, in MOST of the US, there is no requirement to register ordinary guns.
The number of guns owned by civilians in the United States is estimated to be between 238 million and 276 million. There is no gun registration on the Federal level, except for machine guns. There is no registration on the state level in the majority of the states for any guns. This means that most of these are not registered.
Oregon doesn't have registration of Title 1 (i.e., "normal") firearms - only NFA items must be registered. You can own as many as you can afford.
No records, since in most of the US, guns and gun owners are not registered. A very rough estimate in in the millions of women.
None. When made, 99.9% are legal, no matter where made. Just because it's against the law for YOU to own it doesn't make the weapon illegal. Technically the above is correct however as guns are not required to be registered in all states it is impossible to say how many are owned legally. Guns that are owned illegally are obviously not registered so there is no way to know how many there are.
Since the state of Texas doesn't require gun registration, the answer is zero. There are zero guns registered in the state of Texas.
You would have to ask every person in every state and believe that they were telling you the truth to find out.
4 or 5
There are many places where you can find some reviews on cable tie guns. One of the places is on the website Amazon. If you need to find a review, look for cable tie guns there and find the reviews for them.
Look in the classified ads, or go to a horse auction. There are many horses that are not registered everywhere.