LTA would be a wonderful match. I have been blown away by how good those amps sound and how cool they run. David Berning stopped in my room at CAF and we had about a 30 minute discussion about tubes and amps. One of the smartest people I have ever met.
Knowing that tweeter well, you could consider running an 845 tube. The 845 is going to be more linear than a 300B and is going to give you a massive soundstage. The only issue is that they run hot compared to the LTAs but tube life is long and replacement tubes don't have to be $1100 a pair unless you want them to be.
I use 45w 845 Push Pulls to drive mine but they have an 85dB efficiency. Your speakers could easily be driver by a SET with less than 20w.