Because I am in a travelling training and examining job my totals are not representative of a line pilot. However I think between 250 and 300 hours is about right with the amount of SAROps in there being variable depending on how busy your flight is - Chivenor and Valley did over 300 jobs each last year whereas Wattisham was under 200.
Most RAF crews will fly a good proportion of those 4 hours available each day so even if you took out 30 days to weather and serviceability (which is a lot) you still end up with each flight getting through over 1300 hours per year.