Reputable sellers & wholesalers/fastest shipping/ most durable metal

Hello all, I am relatively new to the SS/FRT scene. With that being said I am not at all new to the firearm scene by any means. I have done my fair share of research on the SS and how they work, the kinks, the fixes, etc. At the moment I’m waiting on two SS from DNT to arrive to install, test, and tune. Overall the experience with DNT has been smooth, decent shipping time, package should be here tomorrow and were ordered on the 25th. After I get these installed I’m looking to get into the Glock frt and see how that goes. I have lots of different guns I’d like to try these out in so I’d like to get a decent wholesale price on my next order. What are some good recommendations for dealers that do wholesale or decent sized orders of Precut triggers, SS lever and cam, precut Glock frt trips and maybe some other things I would need to get these up and running. Also what do you guys think is the best material for the SS to be manufactured out of. I have read mixed reviews about D2, 4140, and even some good things about 3d printed CF cams and levers. Longevity is the goal but I’m not above ordering or attempting to make replacements levers if (or when) they become unavailable.

TYIA!