Ok, lots to think about here. I figured 20db would be a lot to ask
out of production unit. Tim's made a couple good points. A Tetrode
may be a good way to go, but I wonder if a 4146 driving into something
else might be a bit cheeper. Maybe a pair of 813s? As I said the 1965
ARRL handbook claims a kw out with a pair of 813s,but I have my doubts.
They are cheep enough - $55 ea at tubesandmore.com The Taylor 572B
can be had for about 200 bucks for 4 of em. Would this be a viable
option?

I wonder if the 4CX1000 or 3-1000Z solutions can be done for a good
cost relative to other implementations. Also, are they easy to get
working? I'm afraid I might end up chasing parasitic ghosts. I am
aware that layout can be critical and would look to clone somebody
elses design that's up and running if that's the way I go.

Thanks for the comments. I thought it was narrowed down to a large
tetrode with a lot of gain or two stages with 4146 maybe driving 813s
or the 572Bs that get run in a lot of commercial rigs. Then I realized
I would have to buy a plate transformer and a chassis and a box and a
whole bunch of other stuff. Right about now some kinda intermediate
predriver to get between the 10w out and the 100w in that I need might
not be a bad deal. Then again I really need to buy from somebody I
trust cause I hear a lot of people whining about used linears they
bought. So nothing is decided.