Several years ago, I posted a forkblade that was rusted, bubbled chrome, etc and was warned by responders "not to use it". I sent the fork off to have the blades replaced and the builder replied, "why? they are sound, just chrome and paint them."
Now, he had the expertise to determine soundness......You will have dome come to the same conclusion whether you do via a professional or personal determination.

to me, the hole looks to be on the outside of the fork leg correct? It also looks like it was a screw hole that was holding something that got torn off. I'd flood the inside of the fork with OA or Evaporust then prod the fork with an awl or ice pick to see if the steel is sound. Personally, If I was convinced it was sound, I'd fill the hole and use the fork.


Just an opinion, I have no training, skills etc, just a "what the 'ell" attitude to such things. 'Couse the replacement fork would be just fine as a rider or have the blades replaced if it's a restoration.