Paint Questions

Here is my original post: As a winter project I have been re-furbishing a mounted plow for my C. I have totally disassembled the plow and have used a wire wheel and a grinding disk to buff/grind off the old paint and rust. As I was going merrily along my way I had been priming the parts so that the metal wouldn't start to oxidize before I got it all buffed and painted. Being a novice to this I made the silly mistake of buying some oil based Rustoleum primer thinking that it would be ideal for this situation (old metal and not being able to get 100% of the rust off). Now that I 2EA
am ready to paint it the proper colors I am having problems with the paint codes. I can find the red ok. In searching for the blue PPG here in Omaha can't find 10067 and DuPont says that the 24160 will react adversely with the Rustoleum. The question is: Does anybody have a reasonable solution to my little problem of incompatability between the primer and the finishing paint? I would sure hate to have to buff all of the primer off and start over. Is there a primer that I can prime over the Rustoleum primer? Is there any kind of paint that I can paint over the Rustoleum primer and then use the DuPont/PPG paint? Thanks for any encouraging advice. Randy