Yes, such are made. Since it's just Windows and Excel (no mention of which version) just about any model will do this work. Here's the list iMac type Windows PC I see on Amazon's best sellers.
https://www.amazon.com/Best-Sellers-Computers-Accessories-All-One/zgbs/pc/13896603011
I have a MacBook Air laptop. I am looking to buy a computer and monitor so that I can work at home using the Windows version of Excel, which I need to have access to at home because I am a finance professional. What would people recommend that I buy? And it isn't possible to just buy a monitor and keyboard that gives me access to the Windows version of Excel, is it?

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