Looking for 1/35 UH-1 decals...

Yup PowerPoint.  It maintains the integrity of the image, but makes it tiny.  I have downsized things as small as coke can labels, cigarette packs, and money.  They come out just fine.  You can see the labels in my Bradley.  

Here are some magazine covers I downsized as well.  They are about 2cm square.

How about some Field Manuals, range cards, DA 2404, and other Army forms.

You can downsize any quality image that can be lifted off the net.

Hey Heavy Arty...............you just said something that made my head ring.............."put the artwork into PowerPoint"??????  that works?  I mean to allow something to be readable in a small size?  I'm sounding stupid here..............but I've been trying to use PS and it just doesnt work when you down that small.  PowerPoint eh? 

Regards
Steve

I don't know of any Huey internal plackard decals either.  If you want to make them yourself, it isn't that hard.  All you need are some good images of the actual plackards, copy them into a graphics program (I prefer PowerPoint), resize, and print them off on computer decal paper.  I make my own decals all the time.  I haven't done internal plackards for Hueys, but have done them for US AFVs.

I have done external marking decals for Hueys though.  I made the crosses and name on the nose for this UH-1H DustOff helo, and all the decals on this White Sands SAR bird.

You can get the decal paper in clear, white, or colors.  It is available in good hobby shops from Testors and others, or online at Papilio Art Supply.  I prefer the Papilio paper.  Of note, unless you have an ALPS 2000 printer, home printers don't print white.  To do white on your decals, you have to print onto white decal paper.

Good luck.

No decals exist, that I know of, for the interior of a UH-1