Just saw that Rinehart carries a slip on for the Breakout. It may be old news by now but i thought I would share it. I ordered me a pair. I had some on my Streetglide for a while. They sounded great. Hopefully these will too.
https://www.rinehartracing.com/shop/softail-slip-ons/

 

I put a set of these on my 2016 Heritage. I like them a lot. They are not quite as deep sounding as the larger ones you had on your street glide. But in my opinion they have a much deeper sound than Vance and Hines slip ons.

Very high quality product.