Couple questions about this hallmark

[Islandmomma]

Reyna Platero Secatero Bolo and Buckle with McGuiness Turquoise

I recently bought this set for my Dad for Father’s Day and would like to find out more about it. I have researched this woman before and found it hard to find comps because she started working in the 70’s. This was attributed to a different artist even though Reyna’s initials are on both pieces. They arrived yesterday and when I unpacked them I was very pleasantly surprised by the weight. They are substantial with the buckle weighing 120g and the bolo weighing 149g. I did find information about …