In the recently posted Nova program, Luke Haag pronounced it CAR-cun-no which I believe is correct. I've been pronouncing it wrong all these years too. I also learned that I have been misspelling the last name of Luke and Mike Haag for as long as I have written about them. I have spelled it Haas because that was a surname I was more familiar with.
My Carcano is a 7.35. Finding ammunition is harder, but finding ammunition that is the correct diameter (0.268" vs 0.264" for the 6.5mm version) is much easier.the 7.35mm rifle is identical to CE139 in every way except for the bore.
I just found this listing for a Carcano short rifle. https://collectorsfirearms.com/1111-italian-carcano-m38-short-6-5-carcano-r27052.html/Unfortunately, it has already been sold. Asking price was $439.95. I would have thought it would have sold for more. I don't see a date for the sale. It appears to be the same model as what Oswald used. It does show that the "Oswald model" does occasionally become available if one keeps an eye out and gets lucky. Had I seen this ad before the rifle was sold, I would have been sorely tempted. I wonder how many of these are in private hands right now.