As mentioned in the last few weeks on this forum the YS Performance business is going through some changes right now. I don't know the status or availability of YS decals. I do know that most of the Vinyl cutting companies that do graphics have YS logos on file and can produce them at a very reasonable price.
I personally have used Kirby's Kustom Graphics
I have also seen exceptional graphics work from the companies below They are in no specific order and i know they are all great companies:
Bad Brad Graphics
http://www.badbradgraphics.com/
Die Hard Graphics
http://www.die-hardgraphics.com/aircraft.html
Aerographix
http://www.aerographix.biz/
Cutting Edge Graphics
http://www.rcdecals.com/
Kirby's Kustom
http://www.kirbysgraphics.com/
I know that there is somebody that I have left out. All of the companies above are great to work with and have loyal following of modelers. The versatility of these companies allow for colors that match Ultracote and Monokote, they also have tons of different ways to shadow and present the graphics. Just contact them and they can help.
As far as Factory YS decals I will check with Richard the next time I speak with him. Right now I personally don't have any YS factory stickers.
Troy Newman
Team YS Performance