Need advise with impedance matching with RF amps and antenae

So, I am building a high powered FM transmitter for out in the ocean.

I found a complete FM transmitter on a chip

http://cgi.ebay.com/Hobby-mini-Stereo-FM-transmitter-module-SMT-2pcs_W0QQitemZ380125287844QQcmdZViewItemQQptZLH_De faultDomain_0?hash=item58813b95a4&_trksid=p3286.c0 .m14&_trkparms=65%3A15|66%3A2|39%3A1|240%3A1318|30 1%3A1|293%3A1|294%3A50

Now, I want to take the RF out from that chip and amplify it so I can broadcast about 500 to 1000 feet.

How many watts and what style of antennae should I use?
I am planning on using a λ/2 length antennae.

Should I put an RF amp Buffer in between the fm transmitter on a chip and the power amplifier?

Can anyone recommend a RF power amplifier that is available on Digikey and is relatively cheap in price that will meet my broadcasting power needs?

Do you have a better suggestion than using that fm transmitter on a chip? I am worried that it might have a piss poor quality signal. I am not sure if it is PLL or not!

Thanks a bunch!

First you need bandpass filter , after RF power amplifier .
1000 feets needs only 1 watt.
And easiest antenna 1/2 wave dipole.