Hi @Cosmos2nd Gen, welcome to the Sonos Community.

For surrounds, I would recommend either the Sonos One or the Sonos Era 100. You can use other speakers such as the Sonos Five as surrounds as according to our surround guidelines: however, unless your room is set up to replicate a private cinema, these would likely be overkill for your setup.

The Era 100 have three drivers and the Sonos One has two, so you’ll have a better soundstage and audio experience with the Eras, but the Sonos Ones are cheaper. It’s up to you which of these options appeal to you, but if you aren’t sure, our return policy will give you time to test the product and return it for a full refund if you aren’t happy.

I hope this information helps!

For surrounds I'd use One SL's. They do not have a microphone built in, but surrounds do not use the microphone.

Thank you, no mention if a sub woofer here?

@Cosmos2nd Gen,

Just to say quickly that Sonos HT surrounds with microphones built-in, like the Sonos One, or Era-100, can have voice assistants installed on them, aswell as on the Beam itself, so if you need voice control to be be available to either, or both those surround speakers, then they are worth considering, plus as you upgrade things, perhaps further along the line, you may prefer to put those speakers into other rooms of the Home and have voice control available then too - so it’s worth thinking about that, before making your purchase decision.

I would definitely add a Sonos Sub (gen3) to the setup too at some point in time. I have both types of Sub, (gen3 & Mini) and both are extremely good, but for your size room I would personally go for the larger Sub (gen3).

Are there stand accessories available of the Sonos one, five etc?

Yes - https://www.sonos.com/en-us/shop/accessories

Also, there are various 3rd-party speaker stands available too.. a simple Google search will find the other popular brands for you to research.

Since you have a Beam 2 you might consider the Era 300’s which will compliment the Beam 2’s ability to process Dolby Atmos. They are more expensive but will future proof your setup. 

Your room is fairly large considering that one dimension is 10 Meters (32 ft). That said a Sonos full size sub (IMO) would be the best choice. If your viewing position is somewhere facing one end of the 10 Meters a Sub-Mini may suffice. Placement (IMO) should be in a corner either to the rear or front of the viewing direction.

However, in the end your budget will dictate what products you buy at this juncture.

Thanks Team, Era 300’s and Gen 3 Sub on there way.