Recommendations on stuff to look at for upgrading a 300B SET amp

I built an Elekit 300B SET amp with tons of upgrades (e.g. Mudorf caps, Takman resistors, Lundhaul power supplies and output transformers, etc.).  I love the amp but I wanted to increase power from 8w a side to 16-25 while staying in the SET camp.  I'm just starting the process of brainstorming. I was thinking of 300B monoblocks,
845 tube integrated or similar.  I want to stay under $5k and would need to sell some stuff--I have a wonderful Primaluna HP integrated with a good chunk of tubes to sell if I did this. I love that amp too but I don't need the power with horn loudspeakers and found the 300B a better match.  

Here are some off the head thoughts:
Manley 300B monoblocks (have to be used to make budget)
Line Magnetic 
Bottlehead 300B monoblock kit

I can do an integrated (but if it's an integrated I prefer a remote) or standalone amps and run them with a Schitt Freya I have for now.  Any advice will be appreciated in my research!  

@oldtech0,  who is building those Parallel Single Ended amps for you?  I'd love to check them out.
Seriously, if you want to continue using SET amps, consider a more efficient speaker. You'll get a lot more mileage for your dollar.
I've read abut the Elekit amp and am thinking of it or the Bottlehead Kaiju as a next kit option. How was the build experience? I've built several kits and have had good experiences with all including a Bottlehead Smash preamp. 99dB sounds like pretty efficient speakers already. I use Pass Labs DIY Amp Camp Monos at 5 watts per side with my 99dB Klipsch Forte II's The 5 watt amps seem to have plenty of power in this setup.