99 TRD 4x4 Front Springs at stock ride height

I'm a new owner of a stock 99 TRD 4x4 with 202k miles that needs new struts and springs. It looks like they are the originals, and even though this truck was pretty pampered before I bought it, I think it's time to replace them.

I'm new to 4x4s, but after research, I want to go with Bilstein HDs since I'm at stock ride height. (AFAIK, the TRD package doesn't add any lift, so I don't need 5100s.)

My dilemma is where to get front springs. I want progressive springs similar to the stock springs that are on there now, but I'm only finding constant rate springs.

I don't plan to offroad this truck, and I live on a very bumpy, mile+ long dirt road, so my main concern is ride comfort.

OEM springs seem a bit pricey, so please advise me on alternatives that are just as good. I'm willing to pony up the money needed for springs that are better than stock, as long as they're worth it.

Please send links and advice.

Thanks,
MF