Pico mast heel

Has anyone replaced any of the parts at the bottom end of the lower mast section on a Laser Pico, please?

We suffered an "unexpected rapid disassembly" at the weekend, and the mast fell down. The lower 2cm of the mast ripped off, meaning the foot wasn't secured to the hull.

It seems the base of the mast is built up of 3 separate pieces that fit onto the bottom of the aluminium tube: a plastic collar, a plastic plug, and another bit of metal tube. See photo below and see what you think! I cannot tell which is the mast tube and which is another tube slotted inside/outside the mast. Perhaps a previous owner made a repair...