Ok Just saw the thread was posted a long time back. But this might be useful to someone else.
Here is how i got one a new one for 50 pounds (around 66 USD).
Keep in mind, i do not live in Europe nor US. I live in a far off island lost in the middle of the indian ocean where everything cost a premium. So, if you are in the US or Europe it should be really easy.
Here is what i did:
look for "rav 4 spare wheel cover" on ebay.co.uk. Occasionally you might get a good deal, i once saw a spare wheel cover going for 15 pounds.
You will see a lot of used ones and if you are lucky like me, you could even score a new one.
Using a company named aramex, i got a local UK address, where i can have my parcels sent and these are automatically forwarded to my real address. If you are in the US, i guess Aramex would not work for you. But most probably you will have a lot of companies doing the forwarding stuffs at a competitive price.
Overall i paid around 60-65 USD for the forwarding to my address.
Total cost : around 130 USD which was much better than was quoted to me by the sole dealer on the island (around 700 USD and as they do not stock it - it would take another 2-3 weeks).