Since you're feeding in 1 Mc/s fixed freq., you might be better off replacing the anode load R with a L/C parallel tuned circuit - and run the amp. in class C. With this arrangement, you won't want a cathode bias R. You can still take the O/P from the anode - or add a low-Z overwinding for O/P - choice depends on the load the amp. sees. It might also be worthwhile experimenting with different screen voltages - with the aim of more output - but keep an eye on the screen current - don't overrun it.
Al / G8DLH