Several red brasses have 4 of those elements, Cu, Zn, Sn, and Pb although not in the exact percentages but fairly close. I looked at
Wikipedia at the last table on the page. Of course, those are modern alloys listed. Before alloy standards came in use, every foundry had their own recipes for metal alloys that varied a little from what the next foundry used. The Fe (iron) in the analysis could be either contamination from the crucible or a deliberate "recipe" addition. We may never know, unless someone comes up with a matching part with known history to it.
Also, did you get a chance to re analyze it with 3 tests in different locations? Just curious.