1526S woofs from Crites, CT-125 Tweets from Crites, 2" compression drivers can be either the BMS-4592, made in Germany so you can probably source them there, or the B & C DCM-50's, which are made in Italy, again, you're closer than we are there.
The midhorns themselves can be had from Fastlane Audio either as a kit or assembled. There are more assembled options out there that are good choices also.
Now for what makes these versions of K's that really makes the system......crossovers....are you going to tri-amp or use one amp?