I had my leaf springs re-arched on my 96 about 4 years ago.
I would recommend finding new springs if you can - or atleast compare the costs of new springs versus re-arching.
My re-arching cost about $300- that included installation and 2 extra leafs for each pak.
If you go with the re-arching process...most definately get atleast ONE extra leaf made at the same time (with the same arch). The extra leaf or leafs will help prevent sagging (over time) and will also give the leaf pak more support for hauling/more weight in the bed. The ride will be stiffer.... but atleast now you can haul A LOT more shit back there. I'd fill up my truck with mulch to the top rails and it hardly dropped any.
Talk to the guys at the spring shop - cuz I'm sure its different than mine was 4 years ago.
When I had the re-arching done - I asked for a 2" lift. When it was done and we picked it up - I was like..WTF???. The truck had about 3.5" and I was worried it woudln't settle down (kinda looked funny with 1.5" lift up front). I had to install 2.5 degree shims to get rid of driveline vibes. After a month or so, it settled down to be about 2.5" of lift and has been there ever since.
Good Luck!