Sub with Meridian M6 speakers

Hi All!
I have been using Roon for some years now. Amongst others I have a pair of Meridian M6 over an MS200 connected with Roon. I would like to add a sub to this pair and could not find a way to do that. Can someone suggest a configuration to add a sub to the M6 pair in the same room and stream music to the whole system through Roon?

You need something like an Audio Core 200 or 218.

@Mark_Hyland thanks a lot! There is also one thing that is not entirely clear to me: Both devices have two SpeakerLink outputs. In my current configuration, I have a SpeakerLink cable to the first M6 and then using the SpeakerLink output from the first, cable goes to the second M6.
Would I be able to use the same setup or do I need to have two SpeakerLink cables to each M6 speaker individually from the audio core 200/218? In the user manual they just show the second option, so I am not 100% sure it will work the same way I am using it with MS200.
Are there some links to e-shops in Europe you can suggest so I can check pricing?