Please note the service is not free and you have to pay for the annual subscription fee. Usually, it will take 1 - 2 weeks to issue a e-cert to you.
If you need a company chop, then you need a digital signature or e-cert (orgainzation). Again, HKP and Verisign do provide such service. Simply click above link.
Insert a graphical signature / chop won't do any good as (1) it would not be accepted as original signature nor accepted by law and (2) you signature may be captured by others and may use it for other purpose.