Similar type of design would be the GR Research NX-Otica Kit at a rated 93db.(Not really cheap). The Alon designer (which used to be Nola... same name only backwards) Worked on the Dahlquist DQ-20 and DQ-12. A sealed base box with a boxless midrange and tweeter.
If you like sound the sound of the Alon have you considered bi amping them? Or looking for a pair on Dahlquist DQ20i and bi-amping them. From my experience it’s hard to to listen to a box speaker after listening to the boxless design.
You're other choice would move to a horn speaker but they will have a completely different presentation