"How would the Klipsch KLF-10 speakers do with low powered set tube amp?"
The KFF-10 speakers would work very well and sound good. There's always a better sounding speaker to purchase but if you like horns, Klipsch is a good way to go. I've owned many. As far as pricing of 2A3 tubes...there are many to choose from at different prices...no problem. I used a 5 watt 2A3 monoblocks with Klipsch speakers.
The KFF-10 speakers would work very well and sound good. There's always a better sounding speaker to purchase but if you like horns, Klipsch is a good way to go. I've owned many. As far as pricing of 2A3 tubes...there are many to choose from at different prices...no problem. I used a 5 watt 2A3 monoblocks with Klipsch speakers.