So I've just purchased a sweet set of headphones (The Gold Plantronics RIG500 PRO) for a specific purpose (work-related), but they are wired.

I'd like to be able to use them to listen to music on my phone but of course my cellphone doesn't have a headphone jack... Calamity!

What are some good recommendations for BT receivers that I can plug into my headphones so that I can listen to my music via BT from my phone?

My headphones use a 3.5mm jack, FYI

I don't mind the look of something sitting off my ear, like the Voxoa BTunes: https://thebtunes.com/products/btunes-flight-adapter-bluetooth-5-0-transmitter-makes-headphone-jack-wireless

But that is a transmitter-type, not a receiver-type. 

I haven't yet searched the likes of aliexpress or anything yet, was after some local knowledge / recommendations first. If there's no decent options then I'll have to resort to using my iPod instead.

Thanks!