All, I have a Enfield I need help dating. I think it’s a Mark 4 made in Australia but I have no idea. The serial number on the receiver is 28523 but the serial number on the end of the rifle underneath the barrel is 28176. Other markings include the 3 rifles with B.S.A. on the barrel as well as saying B.S.A. Co near the trigger. There’s also a crown with BM underneath it as well as a triangle with what looks like the letter C with a dot in the middle of it. All other markings are not legible. Any help truly would be appreciated. A location and date of manufacturing would be awesome. Thank you