For the large resistors R102,R120,.. it is likely about the voltage rating, not so much the power rating. The size could be measured, of needed even from pictures.
Q101 to Q104 should be high voltage depl. MOSFETs. There are not that many to choose from. BSS129 would be a first candidate.
The MOVs are often labeled and this should be a high voltage type, like close to 1000 V.