[pgsmedia]

You know, that doesn't necessarily have to be CMYK.

If it's a big run, you can knock off a quarter of the price by using mixed inks and running it
process Y|process K|PMS(some red)
Your printers only need three plates\inks for that.

Also, a mixed-ink red (PMS+K) will most likely give your curtains a richer, velvet color than CMYK red.

BTW: Do AI\INDD auto-mix inks, yet?

an afterthought, post-posting:
If you don't want the 25% price cut, you could replace that 4th plate with spot varnish for some real POP!
It'll be the same price, but you get 25% more oohs and aahs.