Hi @Stubbs Tristan ,
Thanks for contacting Microsoft Q&A platform.
when estimating the cost of running a virtual machine (VM) in a cloud environment and selecting a Windows operating system (OS), the price can vary depending on several factors, and it's not necessarily the case that all Windows versions will have the same price.
Different editions of Windows, such as Windows Server, Windows 10, Windows 7, etc., have different licensing costs. For example, Windows Server editions tend to be more expensive than client editions like Windows 10.
And as of now the feature of selecting image versions is not available in azure calculator.
You can write a review to the product team using below link where they can take your suggestions and improve the product.
https://feedback.azure.com/d365community
Hope this helps you.