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you would be better off diagnosing the problem and correcting the issue.
This era set rarely needs shot gun replacement of parts.
The contrast issue sounds like a video out tube since the other areas (sync/audio/color) are fine. Lack of hum bars in the pic indicates the B+ is prob ok. I typically look at the B+ voltage and scope the ripple to determine the condition of the B+ supply.
if a new video out tube does not clear it the next logical area to look into is the cathode bypass cap on the video out. disconnecting the cap would confirm this, bridging would not help since is seems to be shorted not open (open would be too little contrast).
The issue I have with shot gun replacement is two fold, often it simply is not needed the caps are fine, but more importantly is when used as a way to correct a problem you end up not learning much (what happens if the contrast problem returns? shotgun recap again?).
So best approach is to bone up on what the clues are from the set and learn the various circuits and how they function. Then with some decent test equipment you can trouble shoot and pin point the offending part or parts.
So back to the orig suggestion, try a new video out tube, if no change disconnect the video out cathode bypass cap, test the contrast control, test the bypass cap, replace if bad.
This take much less time to do than a restuffing of caps. One last problem is mass replacement of parts can create tough dogs out of pushovers IF an incorrect part value is used in the replacement. Not impossible to do. It one reason why unmolested sets tend to be more desirable than "restored" sets, unless of course the work was done correctly and the set is currently working.
Work one issue at a time, get the contrast fixed move to the vert, vert problems are tube/bypass cap/feedback cap/plate load resistor on multivibrator.
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