There are some very cheap no frills option available too - like around a tenner - if you want to keep the budget really low. Chris is yer man for this question, I think. He has been happily blueing his teeth for years!
Article 94: It's OK to drop the cow, but not as a weapon.
Slight change of plans (as happens when thinking audio).
I'm now looking for a reasonable sounding Bluetooth receiver with digital out. Will now hook it up to an old Dac for her. That way she can use a wired USB from desktop computer, as well as phone/laptop etc for bluetooth.