Business Card Design

We have a current business card, (see the attached image & copy of logo), we would like the same design, however, we would like it to be A6 size and on the backside, we are going to ask existing customers to write a one-liner testimonial. This is so we can then pass to another client to say "look what we've done for ..." Can we have the opportunity to quote you?

The back should say:

Name of Business:
What I think of the service received:
Name:
Contact Number: