Good luck with SP4x4. I wouldn’t use them again, ever.
The two different ones on YRM are:-
• new - genuine Land Rover, stripped and hot dipped galv
• refurbed - used ones, chemically stripped, repaired (if needed) then hot dipped galv.
I have a pair of their new ones, but only because they didn’t have stock of refurbed ones when I needed them. Both are hot dipped. Both will be better than what you have now.