For cheap easy bluetooth I've had god luck with adding these two to the original becker.
This was more of a stop gap since everything that I'm looking at is out of stock everywhere.
This one is unavailable right now but worked really well and offers AUX, USB and handsfree input as well:
https://www.amazon.com/gp/product/B07D9JW6S1
This one was cheaper and easier to install as it's smaller and didn't have any additional inputs, but it's a bit more annoying as you have to connect to it each time and we did have to reset it every few weeks:
https://www.amazon.com/gp/product/B07MV115BF
I know this is probably not what you're looking for, but figured it might be helpful considering what the landscape of in stock items have been the last couple of months.
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