Other M is worth the $10 you can get on Amazon. I would recommend the Japanese voice option since Samus's VA is better in Japanese. I would also recommend not looking through what people say about this game, I went through it blind and enjoyed the game.
As for Metroid Prime, although it is store pickup only, Bestbuy lists it used for $30
http://www.bestbuy.com/site/metroid-prime-trilogy-pre-owned-nintendo-wii/9825667.p?id=1218179417229&skuId=9825667
You should check to see if there are any stores nearby with them.
Gamestop is also store pickup only for $50
I don't know if there is a cheaper option. I would look around if I were you.
Edit: Oh, you live in Egypt, never mind the part about Metroid Prime. You can get it off Ebay but it is at least $60 for a used copy.
