Anything is possible with enough time, skill, and money. Judging by your posts, the route you wanna take is all bolt on stuff, correct?
You picked the wrong damn truck. Any form of forced induction is going to require custom fabrication and extensive building on the engine to hold up to any form of high power.
As for cost... paying people to do stuff costs any where from 2x-10x as much as it could cost a skilled, resourceful person to do it theirselves.
Example: My mother seized the engine in here (I believe) 2001 Pontiac Bonneville SSEi, and the dealership charged 9k for the whole swap (factory engine to factory engine). I doubt you will find a dealer that will swap a v-8 in your ranger for you, but with deep pockets... anything is possible.
As for buying an engine from Ford... well, hell I've never researched it before. But I'd imagine it would cost more than you would ever consider paying.
Start using the search function, read peoples build threads. We have whole v-8 conversion and forced induction forums with great threads in there. Browse through them, read every post, and it will help you get an idea what you will/would go through.
Helped/helps me alot when planning my solid axle swap. I don't think I've posted any "how hard is it to do this/how do i do this?" (with the exception of a hybrid toy 8" axle thread, but I searched and found nothing... for good reason I had the concept backwards).
My point is the information is out there. Look in the forums here, the tech library, check out rps, etc etc etc.
But, it all can be done.
Remember: time, skill, money
With enough time and skill, you can do anything.
With enough money, you can pay skilled people to do it (but you need alot of money)
Oh, and skill includes proper tools/place to work...
I hope all that made sense.
Oh, and good luck
Here's something cool, check this forum out:
http://www.rangerpowersports.com/forum/forumdisplay.php?f=202