Marten Design Coltrane vs Wilson Audio Watt/Puppy

Avantgarde speakers work very well with Audio Note. A 2nd hand pair of UNOs
should be within your budget.

Marten altered the Marten Coltrane in 2009 to a higher impedance bass system including new bass drivers and new bass crossover. This was specifically for tube amplifier users. Now the impedance is 6 ohm (4.8 ohms min, with bass-adjust in normal). The original Stereophile Coltrane reviews used the 1st generation Coltranes. These are epic speakers and definately keepers.

Just to clarify I am not a horn guy.

This seriously limits your choice of spkrs.
Adding on to Team212's list & David's AN recommend'n:
Zu
Klipsch (Horn / Scala)
JBL (vintage)

OTOH, I am not sure about the AN driving Tannoy Canterbury. I listened to this combo and, while "nice" the sound of the whole was unconvincing given the stellar specs of the parts...

IMO you definitely need a product that offers at least ~100dB / 1 watt / 1 m or better AND definitely need to try it out. That is at least half the fun, btw!

After all, a 100dB spkr will give you ~88dB at listening position for 1 watt (assuming you're listening at 12 ft away); you'll run out of steam soon over 94dB. And this is for a nonexistent, series resistance /totally flat impedance speaker! While this is plenty loud, remember that 30dB dynamics are very common in music... which brings you down to 94-30= ~64dB