Please note that you are asking for a part for two different pistols. The M/40 is the Swedish Husqvarna licence-made version of the Lahti P/35. The frame-cracking is a well-known fault with the M/40, but not with the 'real' thing. You would have to find a clunker for spares, hoping that the reinforcing fix had been applied to the part you seek. Note that many parts, including this one, are NOT interchangeable between the two pistols - the Swedes made many changes to their version, which is generally agreed to be inferior to the original Finnish pistol.does ane one know of a fix for lahti m40 barrel extension cracking or where to get quality spares?