You may be able to find something that does what you want, but you'll need to free yourself from the word free. there are no free cart services that I know of. They are complex things, and no one is going to do it for you for free. It can get really expensive, indeed, which is why PP can be popular, as it just takes a small percentage of the sale. Most carts require you to pay for them, as well as a payment gateway service, as well as a merchant account for a bank ... All of which represent pretty hefty expenses. So for a small, static site with just a few products, you are really looking at something like PP along with a good dose of manual labor.
Basically, the client has to pay money to make money.