Hotrodding a Wharfedale XP2 box - what tweeter

I want to modify a pair of very tired old Wharfedale XP2 cabinets to be powered speakers for electronic music straight from the laptop, for domestic and small audience consumption, like a poor man's Genelec.

I was inspired by this thread:
and liked Phenoholic Anonymus approach and thought that would be a starting point for a powered speaker, and bought two Sica 8H1CS speakers the other year, but hesitated about buying the Visatons that were recommended because their power handling was so much lower. Then I decided I might go for a biamped approach and bought a batch of four MX40 boards to drive it all.
Is there a better tweeter for this arrangement, which handles more power consistent with the 50W output of the MX40 and working with the Sica (up to 70W), and costs no more than 20-30 euros per driver?