Hiya Liam!
Try these guys first!....if they don't have what you need I bet something thay have will .....alot of helo's have very simular interiors and especially consols!
AWESOME resin helicopter detail sets! I have used thier sets before....very nice stuff!!!
http://www.cobracompany.com/
I have found that some AUTO instrumentation can help?
At better Hobby Shops they have decals for guages and dials and photo etch bezzles.
Look through your junk box or boxes, you will find all kinds cool stuff?
When I was building my 1/35 Super frelon I was faced with the same problem NO detail at all....just old decals that were all yelllow and icky.
SO:
I stole the detailed surfaces from an extra 1/35 UH1-C from MRC....did some thinning, chopping, custom cutting and placed the new parts in the best fashion I could, turned out pretty cool!
Hope this helps some!
Straighten up and fly right.....