The biggest issue might be what sort of backflow preventer is required in your area. If it happens to be RPZ level, that's going to suck another 12-16 psi from your already load pressure.
If not, then I would suggest you look into MP Rotators.
http://www.sprinklerwarehouse.com/Hunter-Rotary-Nozzles-Bodies-s/7572.htm
They are sort of like a rotor that goes in a spray body. They are designed to work on as little as 30psi, with many models designed to work on as little as 25 psi.
Even though I didn't have a pressure problem, I decided to use the MP Rotators to make double darn sure I wouldn't run into flow rate issues. Because I used the rotators, I've got the lawn zones and drip zones on seperate controllers, never have an issue with running both a lawn zone, a drip zone, and use water in the house.