That would have to be some kind of spacer. Make your forks look like they were made for the bike.
Custom fitting a new fork is common procedure. If you still have the original fork, measure the steerer portion. I'm gonna assume you're working with a threaded headset. Transfer that measurement of the steerer tube to the new fork.
I don't know what the normal thread exposure is on a Hiawatha if you don't have the old fork. You will have to find out.
To cut the tube, first make up a cut guide. Run an old headset nut down below the area you are going to cut. Then run two headset nuts just below the cut line and lock them together. One (two if you have them) more just above the cut line with just enough clearance for your hacksaw (or sawsall) blade.
Carefully cut the tube. Use a vise to hold the fork (not too tight that you dimple the tubes) while cutting. Use a flat file to square off the cut and a round file inside the end of the tube to remove any burrs. Unlock the two nuts and remove them. With a file very lightly chamfer the end - just one or two threads worth. You still have one more nut that will dress the threads if the first two didn't do it. Remove this last nut and you're finished. (Except for reassembling and installing the fork.)
Two things can wreck your fork. Trying to hold it with your foot while cutting and cutting off too much of the tube. Dismantle the fork so you can get the tube in the vise. Make sure you're cutting in the right place.
Take your time and you will have a factory looking cut.
Good luck.
Ted