Hi sebeckman,
thank you for your generous offer.
The driver's core is 2450SL, and I have two diaphragm types - D16R2441 and another, a designation of which I do not know, it is Aquaplassed (dome only) Ti diaphragm depicted in my first post.
The wave-guide is, unfortunately, nonstandard in that I have modified B52 - PHRN1014 by (i) replacing the 1 in throat with re-calculated and printed throat 1.5 in and (ii) adding a round-over to the mouth, cf. the attached pictures. As such, I do not believe that there is anything comparable.
Saying that, for my current purpose a measurement of the driver only, e.g., SPL, Impedance would be sufficient.
Kindest regards,
M