Thanks for the answer, I appreciate it. I'll start investigating your recs.
The receiver is a Harman Kardon AVR 210, 40 WPC, this will drive the center and rear for sure.
I also have a old McIntosh 2100 105 WPC RMS (but I think it has a very high peak output...those beer can sized capacitors are there for a reason) that will drive either the left/right fronts or just the Sub. I'll have to experiment with this.
What about the KSC-C1? Is that a poor choice in terms of the match the KLF-10s? I see these going inexpensively.
Thanks.