DYNAUDIO 21 W 54 crossover

I need help with someone that can tell me how to get a crossover for dynaudio sub woofer 21w54 a pair to a box.

scan speak 18w 8545 midrange pair per box

morel st 1308 for the tweeter.

someone told me to get a sub amp and use my old two way cross over.
I like to get all the crossove in the box of each speaker.
thanks for all the help.