I am not sure how "invested" you want to get into this project.
What you need to do is decide how fast am I going to drive and how many gallons per acre do I need to apply.
I ran a 220 for quite a while so I would guess you will probably be running around 8 miles/hour.
You will also need to decide what kind of pressure you want or are able to spray at.
There are charts at the tip suppliers websites.
There is also an excellent chart in the Spra-coupe manual.
I would suggest you will need something like a 8003 tip.
This is a 80 degree tip with a #3 size hole.
The cheapest and quickest way would be to set your rate controller at 10 gal./ ac.,leave the tips in that you have and drive half as fast as you were going to apply 5 gal/ac.
I would suggest that you should get bigger tips but there are lots of options.