High powered single end 300b recommendations

or this one, do not let the ratings fool you, this one will do the job.  

A true SE amp 300B is only 8 wpc , if you go into pure class A around 18wpc 

25 wpc in pure class A solid state like Pass Labs you can operate your Harbeths on .tubes maybe a Ayon Scorpio around 40 wpc in Pentode which is cleaner and better then ultralinear  tubes.

Thank you all for your thoughts.

audioman58 I am actually also looking at an AYON Spirit, which seems like it might be the best of both worlds.

How low do those speakers go in ohms? As others have said, the 300B is usually used as a SET - and then limited to 8-16 wpc. The latter value is seen in parallel configurations. I recall seeing a push pull 300b design but can’t recall the maker. I have a Tektron integrated that uses 2-4 300b’s and gets 16wpc with 4. Highly recommended.  That being said, it also can take 45’s, 350’s, 2A3s, and equivalents.  I got it for the 300b’s, but after some swaping I found I preferred the 45’s. I would listen to a few options before committing to a tube type. 
 

If you do go the parallel route, keep in mind the cost. A high end 300b tube can get over $1,000. NOS is off the table due the popularity, matching requirement, and stigma behind it. If you can’t individually bias the tubes and need to replace a matched quad, then when 1 tube goes bad you’re in for a $4,000 bill. I have over 60 tube bed across 3 systems. I wish someone had told me that when I started  

I've seen as high as 28 watts in a push/pull 300B amp but the sound of a SET amp is at least as much that it's single ended than the tube choice. SET amps are high in second harmonics due a lot to their topology which compresses the negative half of the input relative to the positive side.