hello sit,i dont know what mac's deal is with the mc2300 but i also had problem's with their service dept a few year's ago over that model amp & all i wanted was a replacement meter,i went thru hell with them trying to get a new meter or the old one repaired.
the speaker rebuilder i use is fantastic & has completely rebuilt several older model speaker's for me,jbl l250 ti,mcintosh xl1,mcintosh xl1w,atlec 14's,klipschorn's & heresy's & i think several other's too.
the company's name is MICHIGAN SOUND REINFORCEMENT & their telephone number's are 1-810-238-2772 & 1-810-238-4893, they open at noon i think.
i remember that the type of dual voice coil used in the older model's is tough to find & with the xl1's i had them rebuild they had one hell of a time locating the vioce coil's for the mid's but they did end up finding them & rebuilding the mid's for me.
hopefully they can hook you up.