Ten-Tec is about to come out with a new linear for the Argonaut level rigs. It will be known as the Model 418, and it will provide 100 W output. I don't know if it will be rated for full output on AM (or RTTY or other full duty cycle modes), I haven't seen the final specs yet.
It is intended to match the upcoming Ten Tec 539 QRP rig. The 539 will be a 10 W out unit, so you'd have to dial the Argonaut V output back accordingly.
I believe the 418 will be coming out "soon", and that TT will be taking "pre-orders" on the 539 at Dayton this year. that was as of last October, so of course, schedules are subject to change.
Prototypes of both units were displayed at the 2011 Ten Tec Hamfest. I got pictures and descriptions of the on K4SWL's
web site.
...on edit: Correction, the 418 WILL do AM & RTTY. See:
http://qrper.com/2011/10/ten-tec-ans...att-amplifier/