i'm planning to spend around usd 300 on the deck. Any good recommend?

For the speaker, how about the one from ebay "INFINITY REFERENCE 605CS"? I don't really know how to read the spec.

I'd like to have the sub, but I often use the trunk space and fold down the seat for extra room.

If I will buy a pioneer head unit around 300 with pair of component speakers around 100. What's your opinion to get the best out of it?

Thanks again for all the replies.