About your amplifier, these speakers will probably work very well for you, even if your amp has only moderate damping ability. Most push-pull amps have some negative feedback and low output impedance, so they tend to not be as affected by speaker loads. If your amplifier has high damping ability, all reasonably high efficiency speakers will work pretty well on it. And with 10 watts, it probably has pretty good damping.

I suggest you speak with the manufacturer of the amplifier about its performance. If the output transformer has low enough output impedance, it may be that it will work well with practically any loudspeaker. So ask the manufacturer about the damping factor of your amplifier and whether it has specific loading requirements.