New to all of this, just got an 86 R20 Subruban!

[Nodnarb76]

Hello everyone, after years of having Japanese sports cars (and the car payment that came with them) if have decided to get rid of a car note. After I made my mind up to do this, decided I wanted an older Suburban (pre 1992).
After a month of searching found one that seemed promising. I pulled the trigger and bought it for $2300 and man was I supprised at what I got!
1987 R20 Suburban all original (still has stock radio!) no dents/rust, and everything works! After a few days of cleaning/polishing the stock paint was still in decent shape too!
I am falling in love with this truck! I should have done this years ago!
I am learning a lot about older Chevy/GM trucks and have a question.

I noticed the rear end sags a little, this truck was a trailoring model that looks
like it towed a heavy trailer. Through my research I found out I should have 56" leaf springs in the rear. Are there any other models of trucks/vans that have the same 56" leaf spring that my suburban can use? Maybe something newer that I could get some leaf springs from?

This looks like an awesome forum, glad to be a part of this!