Hi,I need some advice for a complete brushless set up and hardware for this boat,
It's been modified for twin motors. i don't race but i do have a need for speed i have a limit of $1,000
for this project or should i just scrap it and go with another boat,need advice.

I would say two aquacraft motors, esc's and 4s Lipo would make that a very fun boat. Twins are never cheap but that setup would be about as cheap as possible and still make it fun. You are also going to have to have counter-rotating props and cables on one side, if it was setup right it should already have them.

Thanks for the help.
where can i find counter rotating props and what size should i get?

Or two Hobbycity turnigy 100amp esc's with fiegao 9L's on 4s/ 12nimh each

Should i go with an esc with a built in bec,or should i just use a seperate battery?

Up to you, i like bec's cause theres less to mess with, but its up to you. Those escs i listed would work great, i have a 18a one of those on an inrunner and i havent had any problems. Ill link it for you,
[link=http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=4882]2 of these motors[/link]
[link=http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=3728]2 of these esc's[/link]
[link=http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=6346]2 of these lipo's[/link](or if you decide you want to go cheaper, 4 6-cell packs would work as well