You can make about anything work, depending on how good you are changing a bracket here and drilling a hole there. You may have some fabrication involved and you may have to weld to the axle tube, which is cast iron, requiring a higher level of skill.
I would say the most important issues to figure out are:
1.)What is the gear ratio/tire size you want to go to? Do the math, figuring out your desired engine RPM for a given speed and pick the closest ratio to the numbers you come up with. Don't forget to factor in any tire size difference. (There are websites that will help you calculate this. Search the Stovebolt forums for keywords like ratio, rear end, axle, etc.)
2.) What width axle do you need? The full size pickups nowadays have a wider axle that will have the tires sticking out of your fenders. A blazer may be better, something from a rear wheel drive car even closer. (You can spend money having a truck axle narrowed if you want a truck axle.) Ford 9 inch rear ends are popular because they are easy to work on (the guts, I mean) and they were used in a variety of applications, so something from a car may be the same as a 1/2 ton truck, but narrower.
3.) How close will something fit with monor modification? Does the S10 Blazer have the correct width with spring mount brackets at the right width?
4.) What bolt pattern are you planning on ending up with? Carrying two spare tires may be OK until you get around to redoing the front end, but it's a pain for a long term solution. (This is why you see guys go with a Mustang II front and Ford 9" rear, or a Nova front subframe and rear end. Then things will match up better.)
5.) Do you have the torque tube (enclosed driveshaft) drivetrain? That would require a different driveshaft and some modification to the rear of the transmission. (I don't know much about this swap, but someone here will.)
So give us some more details and see who can come up with more answers.
