Here is the link to the one I have. It's very nice and comfortable for her. However it's a little pricey. It's worth it to me because walking is one of Sydney's favorite things in the world...so we use the harness all the time.
http://www.bowsawowsa.com/product_in...851a0fa9b55323
ps. I don't think that this one would fit your dog at his age anyway. Syd is abotu 5 lbs...and it barely is small enough for her.