What turntable to buy to connect with my Sonos Beam?

It depends on how much room you have and if you only want the turntable to use the HT system for audio. Below are suggestions for the Sonos equipment you would need. Any turntable in the $300-$1,000 range would be suitable for your needs.

1. Least expensive would be to use an Era 100 with the line in adapter. This will place an added speaker in the room. If you had room elsewhere, two 100s in a stereo pair would sound great with any turntable you choose. Then you would group this room with your HT for audio in more than one room. Think Sonos whole home audio.
2. The Victrola turntables would be next in price range. From a $300 to a $1300 price range, you can choose one that matches your budget. This will allow you to use your existing speakers for audio.
3. The Port with any turntable you choose would create another clean setup that will use your exiting HT system for audio.
4. A separate room like with the Era 100s, but without the need for an adapter, would be to use the Amp and passive speakers with the turntable of your choice. You can then group this room with the HT room. This would be one of the best sounding setups for records.
5. A stereo pair of Fives with the  turntable of your choice, would also need a separate room, but like the Amp with passive speakers. This would also be one of the best sounding setups. You can also group this room with the HT room

The Victrola turntables are great if that is all you want, but other turntables from Project, Fluance and Audio Technica will give you more flexibility and are used by many. I use an Audio Technica my self with a Connect S15 and am very happy with it.

For Sonos the Victrola Stream are nice, they connect over WiFi skipping all the less convenient options.

https://www.crutchfield.com/p_338STRMCBN/Victrola-Stream-Carbon.html

If you go with another connection method I’d recommend wired, not Bluetooth for minimal frustration levels.

With wired you do need a pre-amp but many good turntables have one built into the base of the unit.

Which one to pick is a tough question, maybe start with your “must have” features like auto-stop that lifts the arm at the end of the records rather than letting it loop until you get back to lift it. I’d look for one that was fully adjustable, to include anti-skating too.

Past that you are in the $200 to $20000 price range. Probably hard to hear any difference in any quality brands above the $500 price point. Read some reviews (Crutchfield is a good starting point) and get your hands/ears on the top ones you are considering and then pick what seems like the sweet spot choice.

In my younger / single / richer days I sprung for an earlier version of this one along with a selection of cartridges for playing different formats. Gads! That thing costs more than the Arc Ultra Immersive set with a second Sub. So don’t go nuts.

https://www.crutchfield.com/p_133GK1210B/Technics-SL-1210G-Grand-Class-Black.html