I've done 10M with KNQ7A the mods are simple but the finals i used are:
RD06hhf as its a better performer at 30mhz.
Final was IRF510, properly matched it does well even at 6M.
a RD16HHF would be a good choice too.
Coils and caps were done with toroids and variables. The VXO crystal
is the bigger challenge for most, I had something that worked well for around
28.400 but a SI570 or 5351 is a good choice too.
The IRF530 I have driven that at 6M and with 24V and .6W drive it's
good for about 9W. The magic is that the gate impedence is very
low due to the input C is high and you drive it like any other power
device at low impedances. It doesn't lack gain even at low VHF.