Late 80s Caterham 7 Cosworth red cam cover headers

[Jacques]

I would like to  replace these short tube headers with a longer unit.  I am pretty sure it's having a negative affect.  The car is stock Caterham LHD long body kit car originally sold to a Dutch builder.  the Cosworth takes up a lot of space.  The photos aren't great but there's a frame piece, a motor mount strut, an alternator and a starter to work around.

 

Question for the Forum is 'Does anyone know of headers that have been produced for this application?'  What is the best way to go?  Any options other than custom?