@ 650, small turbo LS motor, do it cheap and beat it like a cheap wh*re.
@1k then its a budget question. We do LS stuff north of 1k all the time, but depending what you wanna do with it, it might not be the best option. If you want the "easy" 1k with room to build and can cut the check, then its the aftermarket bbc discussion; big cubes etc, big heads, big fuel. We live in a world where Sonny Leonard will sell you a 700+ci motor