Speakers for my Golden tube SE 300B II SE 9w Please help

If you are into horns, I would recommend the oris horn 150 available from welborne labs or any well designed lowther horn including the voight pipe which is real easy to build. The Oris's are the best speakers I've ever heard. If you don't like horns, you can also look into the triangles which got real good reviews in stereophile. The only one I've heard are the tituses and they are awesome for 500 monitors and they were being pushed by custom 2a3's that put out a whopping 3 watts. However, if thats an indication, the other triangles should be better.

Silverline's are a great rec. They're very efficient and tube-friendly. Impedance doesn't dip below 7 ohms. They have incredible mid-range and well-built time-aligned cabinets. Driver quality is excellent.

I use the klipschorn with these amps and they work fine.
But for woofer I use a CJ Mv50 (fantastic).

you may consider Triangle Zerius speakers.
They are affordable and very efficient (93 db).
I have a pair with the Golden Tube and I enjoy it a lot.