I've tried putting several different V6 emblems on my car, but I found only two that I liked and can recommend. Both are chrome finish with adhesive backing, and look like they will last a while.
The "V6" emblem above comes from a Ford Escape. You can get it at a Ford dealer for about $9.00. The part number is shown on the left. For a while I used this emblem to replace the "Ford" emblem on my trunk lid.
I have this "3.8" emblem on my car now. It is similar in quality to the "V6" emblem above and is also chrome finish with adhesive backing. I like it because the red decimal point matches the color of my car. You can buy one on-line for $10.00 plus $4.00 shipping from VMPTuning.com.