Nivomat rear shocks on Grand Caravan


I’m searching for a low cost replacement for the original equipment load leveling rear shocks in my old 2000 Dodge Grand Caravan.  Vin No:  1B4-GP54L2YB-634757

At 140k miles the back bounces a bit and the Nivomat type (the diameter looks large) replacement cost is prohibitive, between 4 to 10 times the typical shocks for this vehicle. Can I replace them with a Monroe product like 58620 to get a better ride and regain some of the removed load capability? Will they fit in place of the original without modification? I don’t use my van for heavy loads or towing. My cheapest option is to just accept the ride of an older vehicle. Are there other low cost solutions? Air Shocks?          

Thank you for your time. 


Mike T.