I deal in surplus IT equipment.
People selling stuff (especially those that don't understand the value of time or knowledge) want to sell it to you for what they think you can get out of it.
Somebody that says "Well, it'll sell for $1500 as scrap plus $2000 for the supercharger used, so I'll sell it to you for $3500" is essentially declaring your time to be worthless.
There are two knocks against this truck. It's super-charged (hard-driven), and likely requires a rebuild; it's also been totaled out. These two problems indicate there are likely further problems lurking that haven't yet been identified. Even if the s/c is worth $2,000 used, it still represents a lot of hours of wrenching, eBay listings, etc.
I wouldn't pay more than 10% above whatever the local scrapyard is paying for 4Runners. My Runner set me back $4200 5 years ago; the dealership I bought my wife's car at a month ago offered me $3500 trade on it.
I'd pass. Better vehicles at your desired price point are available.
