Any GM full size springs from 77-96 go right in. Caprice, Roadmaster, Impala, Delta 88, etc, etc. Chevelle/Malibu/Monte Carlo from the mid 70s will work, too. If any of your local parts places deal with MOOG, you should be able to order new.
Rather than chop stock Caddy springs, why not look at replacing the springs with Impala SS springs. I am told that those springs will fit a Cadillac and lower the front a couple of inches. I am not a fan of chopping springs but then I am of the generation that used an acetylene torch to cut springs. We were sooo wrong.
I used, well the muffler shop I took it to, they used an acetylene torch to heat both springs up on both sides of one spring to lower it. Once it was done, the car wasn't able to roll off lift, it had to be raised by a few personnel and I was driving it out.
Loved how low it looked..
I love your new car.
Clicks all the right boxes on my list!
Your front ride height look just about right to me.
Your rear seems a bit low though. I would check for proper operation of leveling system.
Possible leak in line or shock.
If working and not leaking out, then you lever needs to be adjusted increase the normal ride level.
Because my car is a lowrider style, i want the front wheels to have a 3 inch gap at the top and the back to be lower by 2 inchs... I will look out for holden hq springs , or impala or buick springs to replace the front. After swapping to my 14 inch
lowrider wheels the crossmember hits the ground because springs are to low.
It would be best to have a standard spring at the front that has the same stiffness as a factory one .. Car is currently up in the air at the back lol