It will be interesting to see the rest of the final unit schematic. The VRF150 is a direct replacement for the MRF150 which was used in the TS950SDX. The drivers on the 950 are the 2SC3133's which are on the unobtanium list except from china. Maybe we can infer a replacement from the 990 schematic...
Oh well, it sounded good anyway. The picture shows a single FET driving the 2 finals which would preclude revamping the 950.