Editing Wordpress plugin to make it more complex / developing a plugin for wordpress

General information for the website: Looking to set up jewellery website
Num. of web pages/modules: one
Description of every page/module: The plugin I'm looking to implement (or the best choice I've come across for the job I require) is the fancy product designer: http://codecanyon.net/item/fancy-product-designer-woocommerce-plugin/6318393

Basically, I want customers to be able to personalise the jewellery items. The page would be divided into two halves vertically. On the left half, the customer would see the image of the jewellery item and on the right half, the customer would view the options available for personalising the the jewellery. I've attached an image of what the page could look like.

At the moment, the module specified above, allows for one to type text, choose one of the specified font styles. I require more options to be enabled. The developer of this module has advised that on purchase, the source code would be available, so I believe any modifications would be made to the existing source code, which may be easier than designing an entire plugin from scratch.

But please also do contact me if you are able to design the plugin from scratch for wordpress, if this is easier.
Description of requirements/features: My requirements for this plugin are as follows:

Taking a ring as an example;

- Customer should be able to choose a ring size
-Should be able to type font (which would be limited to maximum number of characters)
-Choose the font style(some new font styles need to be added to the existing font style)
-Choose a symbol (such as a heart)
-Choose material and colour

PS: At the moment, I suppose just the font would show up on the image with the modifications selected. But if you are able to actually create a 3d version of the ring, please do let me know and how much the cost would be for creating this.
Specific technologies required: wordpress
Extra notes: