I wish there was a cheap way to acquire all the small primer 45ACP brass that others are scrapping. It sounds like it would be almost 100% once fired. I have gone to SP 45's to avoid changing size on the Dillon 550B. I don't load anything but pistol on it. .45 Colt and larger are done single stage.
Regarding sorting, I'm sure there are some SP cases mixed with the LP cases I have on hand since I purchased some of it and picked up the rest. I'll let the Dillon find the LP cases that I miss in those buckets.
On a side note, most of the SP 45's I have are headstamped Blazer. I've never been curious enough to check manufacturer. Federal and Speer are next.