That's one of those later UK-spec Raleigh Sports continuation models too; might use the same fork as an 1979/80+ Sports, but chances are it's slightly different. Might even be 24TPI.

As for stems and forks, nope, nothing on hand. Has to be some shops over there filled with 3-speeds to pilfer parts from though. At this point, I'd commit to the stem cut knowing full well that the steerer may be bulged beyond safe reuse, thus making the whole extraction process an exercise in more work than necessary.

Of course, the steerer may still be intact too, making this a venture in its own right. All depends on how much sweat one's willing to put into it, as the trick is finding enough vertical force while twisting to get the stem to pull out.

There is, of course, the possibility of adapting one of Jack the Bike Man's tricks for stuck seatposts: Cut the stem off with about 2" to spare. Pull fork, remove front wheel, clamp fork crown (with padding) in vise. Get deep impact socket just a touch larger than the stem, slide it over, drill a hole through impact socket and stem (but not steerer!), install bolt through the whole shebang. Make another hole 90 degrees to that (and about an inch higher or lower), also install a bolt in that one. Then connect up impact wrench, hit the gas, and pull up. It just might do the trick.

-Kurt