Following link is to a 200 AM class E transmitter, modifiable to 160m, and maybe 80m...
http://www.maxmcarter.com/classexmtr...escription.php
Could be the basis of a project.
The article talks about using PA amplifier as modulation input - which is an intriguing idea.
Watch out George, Mr 'AMR, AM transmitter project may add to the AM ranks.