Cracked turbo pipe, Help needed.

[Dupin family <dupina@crisny.org>]

Looking for 5KTQ ('86) good used turbo exhaust pipe, the one that
connects the turbo to the cat with the O2 sensor and the wastegate
connections.  Mine is cracking at the O2 sensor connection.
    Is this a generic problem?  Should I suspect my engine mounts?  I
replaced the turbo side mount approx 8k miles ago.
    Are there any fixes (reweld), preventive measures (reinforcing
brackets) available?

    All suggestions welcome.

    Thanks in advance,

    Phil Dupin