Need to paint a wood subfloor fast!

I am planning to rip out the old carpet in a beach house den and just paint the subfloor off white. I am very short on time and money, and the house will be torn down in about 5 years. I want to paint a compass rose in the center of the floor. Can I get away with 1 or 2 coats of tinted primer and 1 coat of latex flat, with 2 coats of polyurethane over it all? The floor will receive moderate use in the summer only. Here is a link to the design if you are curious: http://www.istockphoto.com/file_thumbview_approve/6396209/2/istockphoto_6396209-compass-rose-ancient.jpg

Any opinions about latex vs. alkyd, number of coats, etc?

Thanks so much!