I found a nice blue spray paint at Douglas Hardware that matches the dome vinyl I got from Tim almost exactly. It is Valspar All Purpose Gloss Blue. I was using the Rustoleum Deep Navy initially, which is probably more spec accurate, but it was way too dark next to the vinyl.
I also fabricated a lens for the radar eye out of a 2 liter bottle. I used the radar eye to mark the rough size and then trimmed it down. I painted the backside with Testors Gloss Black model spray paint. Viola! Instant lens!