[Friday]

some of those 20s forks have 3 tubes sleeved over each other and theres a pin running thru the cast ....below the bearing surface flat.
If you have all the paint removed youll see. Looking up the centre you should be able to see it . That thing should press out. ***unless** theres some welding they did before attaching the tops of the legs.
My ones are bead blasted so I cant tell if its welded.

chuck up a pic , if yours are sleeved you might be able to use the existing one as alignment for an extension replacing the damaged section.

I should get my lazy arse to take a pic of what my forks look like. I think its 3/4" inside 1" inside 1 1/4"

 

[Friday]

Im guessing the frame had the neck screwed over with cups for tapered bearings.
Id get a new tube threaded same as original and use the existing 1 1/4 inch tube thats already in there as the seat and then have an internal tube to stiffen it all up. just like VL HD frame tech.

***I wouldnt press any thing in = the cast would shit itself.

the bike weight rests on the casting which rests on the fork legs.
the stem keeps it all aligned , those days theyre pretty light bikes thats why theyre not solid.
Use the top handle bar tree for alignment and braze from the bottom.
Im guessing your forks have the pin to stake it all down.

Only suggestions or ideas here
Damn shame about the frame . Im on the hunt for 1 at the moment .
see the pin just below the bearing surface? right pic