Well G21 the only thing I know about the 45 Super is what I've read and remember out of that which isn't much so I took a few minutes and looked up a few things for you .
The short answer is no because if from what I recall and from I have just read the working pressure of the Super round needs a slightly thicker case to contain the pressure safely But , and this is a big but if you are satisfied with loads that are in the very mild range "for the Super Cartridge" with lighter bullets for the Super you could probably get away starting out with brand new 45 acp cases use light loads and perhaps have to switch to a lighter recoil spring for them in your 45 Super chambered gun . The downside to this is you would get a short case life , I am guessing maybe 6-10 loadings before the mouth started to split and you had to throw it away . You would wind up with the equivalent of say a 45acp +p+ round , not quite Super power but more than you could get from an acp chambered gun , it probably would make a nice defensive round from humans and thin skinned light Skeletol predators like a cougar .
Basically what you would be doing is hot rodding a 45 acp without worrying about the gun itself as long as you stayed within the low end of Super reloading data , but you would be abusing the case beyond what it was designed for . I doubt your safety would be in much jepordy . The reason I say this is after doing some searching on the net I have 1 found very limited data for the Super and 2 much of what I have found for light 185grain bullets is almost matched with loads for the 45 acp+ loads the data is virtually idenetical with Power Pistol Powder .
An example is data I found on handloaders.com , there are loads for the 45acp P+ with 185 gr JHP and Power Pistol and some for the Super with the same components with the source of the data being listed as Alliant which I can't even find data on their site for the Super "perhaps they removed it due to lack of interest" . Anyway they list a max load for the acp +p as 9.1 grains with 21,000 cups of pressure and a starting load for the Super at 9.5 grains velocities are 1,075 for the +p and 1,105 for the Super . I doubt with new brass that 1/2 a grain is going to damage anything .
Now I also recall an article on the round and using 308 Winchester brass to make your Super cases , you see all of the 45 autos including the ACP have the same rim size as a 308 . Take a 45 acp shell holder and slide a 308 brass in , it is a perfect fit . The 45 Super is suppose to have been derived from the 451 Detonics Magnum which acquired it's cases from 308 brass .
I think this is the ideal way to use something other than factory Super cases as the web area of the 308 cases is suppose to be a tad thicker to contain the pressures .
I have never made cases from another caliber so I can't help you as the how to's etc .
The best way to get your cases would be to go to www.midwayusa.com
they have Starline 45 Super cases listed as in stock or you could go directly to Starline . Starlines listed Web price is about $8 under what midway sells them for for 500 pieces .