13.56mhz transmitter
By design, the amplifier output power is limited to a few mW. Fortunately this assures survival of the 2N2222 which won't be able to deliver the said 8W output, at least not in a linear PA.
If I remember right, a 13.56MHz PA has been discussed some weeks ago at EDAboard, I suggest to search a bit more thoroughly.
When extending RFID operation volume, the respective regulations for maximum far field should be observed (if a legal application is intended).
As another remark: A 13.56 MHz "antenna" should be regarded rather as an inductive coupler. It is used in a resonant circuit and the input power is mainly consumed by resistive losses. With a suitable coupler design, it's not necessary to dissipate several watts for a 1 m range to my opinion.