It's possible to get a tattoo of praying hands with a rosary by finding a tattoo artist with the desired design in his portfolio. Another option is to commission a custom tattoo.
Getting a custom tattoo involves asking a tattoo artist to draw a specific tattoo, approving the design and having the artist place the design in a preferred location. Finding a tattoo artist who already has a design of a rosary and praying hands in his portfolio may be a less expensive option, as commissioning a custom design typically requires extra time. If an existing design is not perfect, alterations could make it just right.