Irrigation Backflow Preventer - Repair or Replace with Reduced Pressure?

I have a question about my lawn irrigation backflow device. I love in a semi-rural area, and am on a well. I recently broke a test nipple on mine while digging around. The model I have is a Febco 805y double check valve. It is underground, just outside the well pump house. As I researched backflow devices some, I learned that mine is considered "obsolete" and has been replaced by reduced pressure models for safety reasons. So instead of fixing my double check valve model, I am wondering if I should have a new reduced pressure installed. Some facts which might be relevant: As mentioned, the property is semi rural, and is serviced by a well and septic tanks. I do have a grass lawn, and I do fertilize the lawn a couple time per year.

Any knowledgeable insight is appreciated. Also, some idea of the cost of the unit and having it installed would be helpful.