Things to consider beyond fork diameter, length, and axle diameter: axel length, brake mounting, brake spacing (for disks), speedometer mounting (for street bikes), fender mounting, spring and damping rates (sized to bike weight, rider weight, and type of riding). Probably others. Best to swap an entire front (triple, stem, forks, brakes, wheel or at least hub) or stay with repairing the original.
On my present build someone had swapped in wrong diameter forks (bad enough) that had leading axle giving way to little trail (unstable). They cobbled up some steel adapters to mount the original calipers and modified an axle to force a fit. Then to try and control the inevitable tank-slappers fom too little trail they weled on a steering damper. They did at least fit up a front fender from the donor bike. They also mounted the speedometer drive upside-down (haven't figured out why yet). I just swapped the entire front end to a GoldWing set that the calipers and wheel fit and happen to have the same stem dimensions. I'll still have instrument and light mounting issues, but have the donor bike components to help me work that out. If I had found original forks, I still would have been forced to replace the triples as they had spread the originals to accept 1mm larger diameter fork tubes. I had most of the GoldWing parts on-hand anyway.
Sometimes we just have to wait for the right parts to turn up.
Kind of like the fun of trying to fit a JD 216 48" deck to a 345. It can be done. Eventually.