Does a service exists that gives the ability to create a PDF document with clip art in a website owners library?

I apologize if the title is terrible. I am asking for my mother who runs her own online store providing designs for printing such as greeting cards table cards and similar. This is a one-man show, so the budget is limited.

She has a lot of documents with assorted designs that can be printed where you manually cut out the items you want, but they want to allow the customer to choose it themselves to avoid overpaying for design the customer is not interested in and all designs are chosen by the customer.

What we envision is a very basic Photoshop/Illustrator/MSPaint where you have a selection of items that will be put into an easy to print document.