numbersman

I'm looking for some input on pricing some silkscreening of small copy on approx. 1100 interior plaques. I have to price silkscreened 1/4" tall room numbers onto acrylic interior plaques and I'm wondering the best way to go about pricing the materials and labor to do this. All the numbers will be different so should I use a square inch price and what would should that price be or does anyone else have a better way to cover the cost for doing this?