That hasn't got a lot of miles on the clock!! It looks as though it was shipped out of the works, left to gather dust, then you bought it - you jammy little dodger!
Those CDA valves show no sign of distress, nor does the panel.. I've seen those valves so full of "tea stains" that you couldn't see inside, and the panels burnt to toast, but perhaps one good give away is the wiring, especially fly lead plug ends, which tended to turn brown and go as hard as pot.. Even the yellow "ribbon/tape" to the CRT still has its three CD output leads safely ensconced within - these used to de-laminate, change colour, go gooey and allow the leads to hang loose.
One thing about this chassis, being the more modern tripler derived EHT, is that it always seemed less stressed in every sense of the word, as well as being to work on.. Also, being single standard, it was much less complex and lower component count.
Very nice set indeed..... Does it still possess its original CRT?