There are several options available. You noted Spax. There is also Protech, GAZ, and AVO (though AVO recently closed its doors so they will only be available while they last). There may be other options as well. I believe all of them at least have options for adjustable spring perches and have adjustable damping.
I got Protechs from SJSportscars (
https://www.sjsportscars.com/) and I'm pleased with them. Kelvedon (
https://kelvedonlotus.co.uk/) offers a few choices including standard replacement shocks. Other than those standard replacement shocks, I believe Spax are the only ones that offer shocks for the stock 2.5" dia. front springs. I believe the rest take 1.9" or 1 7/8" dia. springs. Spax also offers front shocks that take the 1.9" springs.
There are nearly infinite springs choices you can make. In order to get the nose down, you're going to have to use shorter springs. You can cut the stock springs you have (raising their rate) or get new. I've been using 160# x 10" front and 115# x 14" rear (my spring perches are all the way down so I wish my springs were shorter). r.d. enterprises (
https://www.rdent.com/) sells Spax and shortened front springs as well as Spax rear shocks with springs.
Unfortunately, Dave Bean Engineering does not keep a web page but I would advise calling Ken at DBE (209-754-5802) and seeing what they have.
Springs really is a big subject and there are a lot of differing opinions and personal choices. You might want to do a search and see what others have to say or you can get advice from Ray (at r.d.), Ken (at DBE) or the people at SJSportscars or Kelvedon. I left out Lotus Supplies because they have been selling AVO and they are sold out of them.