I don't recall If I purchased from Rambo but there are plenty of places to get springs and supplies. I have purchased a number of items from Rochfordsupply. I have post in here somewhere. I basically rebuilt my bench seats from almost nothing.
I do recall the replacement springs are different gauge then what GM used back in the day.
https://rochfordsupply.com/products/...lV4k0HV78h0Utw