Tuckstir Cool to see you got more kits in - more UK flags to come? I still dig the SG's finish - Like a mini with a Union Jack on the roof, it just works!
The strat geeks were drooling over callaham blocks (non leaded steel) : https://www.callahamguitars.com/tech_blockdetails.htm. That's one thing still original on my strat (possibly the only thing ?)
Terryd.co.za do have trem springs (if in stock - https://www.terryd.co.za/gptsbrie.html), it'll be a LOT cheaper that Dimarzio re-branded ones. Gear Junkie also keeps the terryd springs in stock.