Hey @BlytheEcho, pretty belt.
So there appear to be a few things going on. Did the salesperson happen to explain that there are two (known) Roger Skeets? Roger Skeet Sr. worked for the infamous trader C.G. Wallace and did not hallmark his work. His son, Roger Skeet Jr. was born in 1932 and marks his work with “R S”. Both are well known for their concho belts.
There was also a period that Jr. marked his work “R SKEET JR”, as seen below, on this first phase revival belt crafted by him. In this instance, Jr.'s hallmark with the broken “E” dates this belt to the 1950s. (Hougart’s 4th Edition P. 316)
The buckle from the belt you posted certainly is characteristic of Jr.'s work. I found the photos below of what appear to be the same belt.
@TAH owns a lovely buckle crafted by Roger Skeet Jr. While we both share a passion for Navajo crafted adornment of the waist, he’s much more knowledgeable than myself, so perhaps he’ll chime in to set me straight, but the buckle on the belt you shared does appear (to me) to be a Jr. work, taking into account the craftsmanship, style, and hallmark.
Below are a handful of belts made by Jr.
Jr. uses many of his father’s stamps and the style of both Skeets is undeniably similar. Concerning the belt you shared, the cast(?) (Feel free to interject @mmrogers) butterflies (or spacers) are throwing me for a loop. While there’s no way to be certain, the butterflies and conchos just don’t seem correct, but please know that is simply my opinion, and I’m no expert. I did find the photo below of a buckle that resembles the conchos. While not a dead ringer, it does bear similarities.
As well as this listing photo for a butterfly of similar design. The listing states that this is “From the estate of Arnold Goldstein, of James Reid design”.
Arnold Goldstein, which you may already know, was a famed New York based designer. In 1968, he, by chance, met then unknown designer Ralph Lauren. From then on the pair worked together and have performed some not so admirable work (in my eyes), copying original Navajo designs and semi-mass producing them. 
James Reid, who you may also be aware of, was somewhat renowned for his belts and accessories.
Here is a Reid belt.
To my knowledge, James Reid Ltd. is no longer around. Below is an interesting article concerning him.
All of that said, I feel the buckle on the belt you shared was made by Roger Skeet Jr., but am really skeptical of the conchos and butterflies. We’ll see what others have to say and share. Thank you for sharing!