Alternatives to KYB?

My 68 Cuda's running KYB4509 and KYB5511 shocks on a pretty stock set up. Up front I've got BFG 215 70R14 and in back I've got 255 60R15. I checked the old receipts from the previous owner and looks like these were bought in 2002. I can't say how much it was driven since then (I've only had it a month so far).

The ride is pretty harsh to say the least and I'm slowly making my way through the car to improve the ride since this is now my commuter. It's meant as a driver, not a racer so I'd like it to feel as such though I don't want to drive a boat. The majority of the stock suspension was replaced/rebuilt so I'm not too worried about that just yet.

Before I run out and just replace the same shocks, any KYB alternatives that I can try w/o making any mods to my current setup? Thanks in advance. My lower back will thank you.