Thanks very much for sharing that vendor for acrylic windshields which I've definitely saved for future reference.
As for the elusive "elliptical" windshield frame/railing material, it is still being produced and distributed as I found while researching a source for a short piece of it to complete the gate that was missing on ours when we acquired it in 2015. I used takeoff measurements of our XK-22 windshield framing to determine that the size used by Chris-Craft is .750 x 1.0 inch (19 x 25 mm) in 18 gauge.
ASTI Products (American Stainless Tubing Inc.) manufactures in the U.S.A., an elliptical railing of 304 SS in 36 sizes and in seven gauges. www.asti-nc.com/tubing/elliptical/ Of these the closest in size is their .750 x .985 inch.
Because they only deal in large volume business with converters and boat manufacturers, I found myself searching for a finished, packaged piece and finally came across a grab handle with the matching specs. I ordered it, then cut and finished it to fit. You'd have to look very close to see it has a slightly different (newer) sheen than the rest of the 45 year old rail.
As for those XK-22 owners looking for a complete railing frame, I'd suggest using these specs to do some further online and local boat yard research or chatting w ASTI to follow the trail to fabricators capable of supplying it.