Rams are easy to ship. First you will need to get a 7"X7"X6" USPS Priority Box. They are free of charge and are available at your local post office. Secondly you will want to line the bottom, sides, and then top with styrfoam. You can get a 4' X 8' sheet of R5 (insulation value) at Lowes, Home Depot, etc. for around $10 and that should be enough to do MANY boxes. Cut two 7" X 7" pieces, one for the bottom and the other for the top. Put the bottom piece into the box. Next make the sides by measuring and cutting. After that put the fish into a single bag. They are still small enough that you can put them all in one larger bag, which you should be able to get from a local pet store. Fill the bag with 82 degree water, put the fish in, and then add a Bag Buddies tablet, which helps keep the water "clean" and oxygen enriched. Make sure the bag has 1/2 water and 1/2 air with that many fish. Tie up the bag putting rubber bands on one end. Then invert this bag and place it upside down into another bag (the knot from the first bag should be facing down). This helps to prevent air from getting out. Then tie up the second bag and put rubber bands around that as well. Wrap newspaper around this bag and tape it off. Then put it into the box and put newspaper into the box if necessary to provide some cushioning. Place the lid on top, close the box, and tape it shut. Pretty simple this time of year. Don't even need to add heat packs.
I had 15 quarter sized angels sent to me last year and they were all in the same bag, with no oxygen added, no Bag Buddies...just fish and water. Long story short they were in the mail for 5 long days as they were sent to the wrong address. The temps were in the low 90's, no cold packs were used. All 15 arrived alive and were VERY eager to see food. Had them spawn for me 4-5 weeks later.
How much were you asking for each fish? Shipping shouldn't be more than $10-12.