There is no doubt you will need good seals on caseback, crown, pushbutton and crystal.
At this age all of the originals will be useless.
So you will have to get a new crown and pusher fitted as a minimum, because it is very unlikely anyone can find a replacement seal for the vintage patterns of both that the watch is fitted with. And unlike (say) vintage Omega parts, there are no direct replacements readily manufactured now.
Personally, I wouldn't do that.
D