To answer a few of your questions, this type of functionality is set for a future release but there is no confirmed date on the release.
On the front end there is a current workaround to integrate this type of functionality for now. The Products details page and the cart would have been customized in order to achieve this.
Also what kind of intergration would you need on the backend? Also can you open up a support ticket so we can better assist you?
Please let me know if you have anymore questions. Thanks so much.
All the best,
the Telerik team
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