Yo,
Quite a few products have this statement because of the RoHS/Lead Free compliance.
Final products have a maximum lead allowance and MCU allowance is now zero.
These parts usually have their Lead Free replacement part number.
This is not changing the MCU inside, just the package.
As far as I know, the RF2 is still produced. Still, you can check with your distributor to be certain.
You can also go to the S08QG8. Small and power efficient. You can add a ZigBee transceiver when you need wireless.
Cheers,
Alban.