Omega 165.001 Cal. 552

Hello everybody,
I bought last year an Omega Seemaster Turler 165.001 with cal.552.
It was time for my to give it to my watchmarker because I had some trouble.
When we open together my watch, we saw rotor was look like little sanded (previous bad reparation).
For this reason I would like to change it. (72205631026 / 563-1026), but my part is look like pink and I check in Web a similar.
They said "red gold - plated", I cannot imagine a mouvement in red gold plated, normally not?
Price is very expensive...

https://www.joseph-watches.com/all-products/omega-cal-563-oscillating-weight-1960s/

Thanks

Georges