I got a LNIB Astra A75 9mm that I loved. A short time later I saw a .40S&W complete upper for the A75. I bought it and it fit perfectly. Even the mags are marked for 9mm or .40S&W. It is truly a gem and with the all steel weight it makes shooting the 9mm feel like a .22 and shooting the .40S&W feels like a soft 9mm. Excellent gun.
.40S&W slide with wood grips:
same gun with original grips in 9mm: