4.3 vortec?

[Primer69er]

i've been searching a while but cannot find what i need, a friend of mine told me he has a 4.3 vortec from an s-10, that has a 700r4. and he will sell me it for $300. the questions i have are this
1. did the s-10 ever come with a 700r4?
2. is $300 a good price?
3. my 69 has an inline 250, no power steering or breaks, what will i need other than the motor and tranny, for this swap
4. are there differences in the 4.3 vortecs, that i need to look for to be sure im not getting a crap motor.
5. will it be hard to hook up the computer and fuel injection.
6. will typhoon/syclone parts swap over?

sorry for all the questions, but i would like to know some things before forking over 300 bones. thanks in advance.