The 'Shears Coat of Arms'
Many places on the internet offer to sell you 'the Shears coat-of-arms', including some with reputable names like Burke's.
Coats-of-arms are granted to an individual and his descendants, not to a surname. Therefore, unless you can prove that you are descended from the person who was granted these arms, you shouldn't display them. And you certainly shouldn't be sending money to someone who is trying to sell you something which is not rightfully theirs to sell.
For about the same amount of money as an Internet shop will sell you someone else's arms, you can have a coat-of-arms of your very own. The following sites will tell you how:
If you are in Scotland:
If you are anywhere else:
The South African Bureau of Heraldry (you don't have to be South African)
(but you will need this form)