Charcoal, 34 bytes

ＮςＡ²ξＦMDCLXVI«×ι÷ςφＡ﹪ςφςＡ÷φξφＡ÷χξξ

Originally based on @CarlosAlego's answer. A port of @xnor's Python solution is also 34 bytes:

ＮθＡ⁵ξＦIVXLCD«←×ι﹪θξＡ÷θξθＡ÷χξξ»←×Mθ

Charcoal, 34 bytes

ＮςＡ²ξＦMDCLXVI«×ι÷ςφＡ﹪ςφςＡ÷φξφＡ÷χξξ

Originally based on @CarlosAlego's answer. A port of @xnor's Python solution is also 34 bytes:

ＮθＡ⁵ξＦIVXLCD«←×ι﹪θξＡ÷θξθＡ÷χξξ»←×Mθ

Edit: A port of @xnor's other Python solution turns out to be 33 bytes!

ＮθＦMDCLXVI«×ι÷θφＡ﹪θφθＡ÷φ⁺׳﹪φ³±¹φ

Try it online! Link is to verbose version of code. Note that I've used ⁺׳﹪φ³±¹ instead of ⁻׳﹪φ³¦¹ because the deverbosifier is currently failing to insert the separator.