I'd be more concerned with the dip at 6.5 kHz. Have you tried moving the measurement mic position to see if it's an artifact?I'd look at 1.6 kHz for a starting point on the crossover, if you're doing a passive crossover then the 800 Hz resonance of the Beyma will need an impedance notch filter. I'd look at Wayne's crossover document for help with that.
http://www.pispeakers.com/Speaker_Crossover.doc
Jeff Robinson