Hello, I need advice regarding KLF 30 height speakers. My current setup is KLF 30, KLF-C7 and KSP-S6 classic 5.1 setup. I would like to add surround high 4 speakers. I don't have enough space to use KLF 10 or 20 as back surround speakers. What would you use instead ? Purchasing additional KSP-S6 will be extremely hard, they are very rare.