Fuel Injector Module

I drive a 2002 Pontiac Grand Am SE with 60,000 miles. 4 cylinders. Yesterday it stalled while I was driving it and had to coast it off the road. I had it towed to a repair center and they said they had to replace the Fuel Injector Module and the Fuel Filter. With parts, labor, and tax they said it would cost me over $900. I'm just wondering if this is a reasonable estimate. Should I take it to the Pontiac dealer for a second opinion? How much does this normally cost? Thank you so much!