I think I found a picture with the Dominican Republic P-51 nr 401 and 403. When enlarging the picture you can see that the outer ring on the roundel is darker than the inner circle. So I’m pretty sure this is the old roundel.
Another colourisation from a National Library of New Zealand photo, this time featuring RNZAF Lockheed Hudson IIIa NZ2063 in Fiji in 1948 wearing the International Search And Rescue colours.
source FB
[ATTACH=CONFIG]258085[/ATTACH]