You have a Guernsey (Channel Islands) produced 465. I would fix that DC Ripple first of all if I was working on it, but that is just how I roll..
You can also see if have a sawtooth waveform at collector of Q1038. I would start looking at the A&B Sweep generator circuitry for all the correct trigger, reset and unblanking signals and then for any Horizontal Amp issues.
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Michael Lynch
Dardanelle, AR
Michael W. Lynch