Where would I typically get these?
I'm after a right-angled one.
The Corgi monkey that fitted the boiler drilled the hole for the
flues dead level, and so with rain in that direction, it blows
into the boiler, runs past the electronics board and out the bottom,
staining the wall.
Rather than redrill the hole, which is probably the right solution
(but fun, as the wall is 500mm thick), I was wondering if I can get a
one pointing down and out at 45 degrees, rather than straight out as at
the moment.
Right-angled would do, but obviously cause condensation on the wall,
which I'd like to avoid if I can.

(there is not a footpath or anything immediately below, and it's at 3m
high anyway, so there is no concern about singing passers by.)