I think such a device would be called a bluetooth transmitter. Amazon stocks them...

I recommend the Avantree line of BT transmitters.  They have enhanced range (up to 30m) - a big plus.

Avantree Oasis Plus claims 50m. It supports aptX-HD, aptX Low Latency and standard aptX -- to a compatible receiver or headset of course.

Used in conjunction with an Avantree AS70 adapter it can deliver aptX-HD throughout my entire house.

Wow, thank you! The Avantree Oasis Plus looks great. If I understand their website correctly, it looks like I’d choose to connect this to the the Sonos Connect digital audio out optical port. Is that correct? If so, would I be able to listen to any Sonos music source or just the turntable (TT) the Connect it’s connected to? Also, would there be any additional steps to going back to listening to the TT without the Bluetooth headphones or will the system be setup for either experience?

If I read the manual (https://a.storyblok.com/f/58706/x/cfc79c92e1/avantree-tc500p-user-manual.pdf) you’d connect it to the Connect’s optical out. I’ve never used the optical connection on my Connect, but I have no reason to believe its output is any different from the analogue connection. So you can hear all Sonos sources and your record player.

The Avantree looks very nice. Looks like it’s not only a bluetooth transmitter, but also a bluetooth receiver - a part you do not seem to need. So maybe there a cheaper option?

Most BT transmitters which support digital connection use optical. I’ve had Avantrees on ZP80s before, and presently have an Oasis Plus hooked to a Port via coax/optical converter. If one’s looking for audio quality via aptX (ideally aptX-HD) then it makes sense to connect digitally rather than go through an extra DAC and ADC.

Avantree is more pricey but I’ve tried and jettisoned a handful of cheaper BT devices which often had codec negotiation problems, i.e. they’d not pair at the best available quality.

If aptX-HD isn’t a requirement I’d suggest looking at an Avantree Oasis (not Oasis Plus) or Avantree Audikast.

The Avantree Oasis Plus worked like a charm! I connected using the optical cable and was up and running in less than 10 minutes. I haven’t had much time to play with it yet but so far the sound quality is what I expected and the range is impressive; pairing to my existing Bluetooth headphones was effortless. The micro USB charging cable they provided was a bit short at 3 feet but I have plenty of those laying around. This was the perfect solution for what I was looking for. Thanks all for the help!