TRZ are probably considered the best. They are light and well made. There are some other brands out there that are good as well and some are a little beefier if a lot of street driving is your thing.
They do not list a part number on their website only by description and picture, which is tubular control, arms, 68 to 72 GM, A body stock style coil spring complete kit. They list for $950 which is what I paid.selling them for $750. Plus shipping.
Shaves about 20ish pounds off the car, and much added caster for better straight line tracking and stability
Tom has what you need and they are priced right. You can run either spring style with his. Stock or coilover down the road by adding their cups. We started out w stock style on our 69 then switched to coilover when we put them on the 72.
The TRZ are a great choice for a track car,...and light street use imo,..I prefer the Global West for dual purpose applications,..The TLC series has no sway bar provision where as the street series does,..you will not find a better built US made arm for the money imo