Add booking box to header image section

Hi, I have a website https://londoncollection.uk/ and I want to add a booking box widget on the right so it looks like the photo attached.

I already have the widget to display this booking box, so there is no need to re-create that. All I need is a widget area (or another way) to display it on the header area. I assume you will need to create a child theme to do this. I am using the twentyseventeen theme. This needs to work in desktop and mobile (you can see it works well already as the box is currently placed on the "why choose us" section).

Thanks