Sean - those look like the "brushed aluminum" finish which are on the ones which I have on the set on my 73 914-2.0 since 75 or earlier.
To check, it will have tiny parallel ridges on the unpainted aluminum areas.
If it is the brushed finish - for those potential buyers out there:
A. - These are the true original Rivieras made for the 914, based on the smooth angled outer lip of the wheels at the tires (later "fake"/repro Rivieras have an up-turn "L" at the rim edge). Although he doesn't show the original plasti-chrome center caps with the "R" logo, there's a pic of mine below for reference.
B. - The brushed finish were far more rare than the polished version, if you like the "satin look" finish. However, they were all aftermarket wheels - not a Porsche/VW factory option (although some dealers sold them back in the day).
C. - The finishing process is
different than for the polished version, wherein you'll need to clean it up with 000 steel wool, a fine wire brush or wheel to get the oxidation off, then polish to
satin finish with Simichrome or similar chrome polish, etc. However, you need to be
very careful to neither brush/polish off those tiny brushed ridges, nor to deepen them with the wire brush/wheel.
Pix of my polished aluminum Riviera alloy wheel with center cap:Click to view attachmentClick to view attachmentThe original background areas' color on these was a satin black as shown on these, but mine are a bit rough & haven't been cleaned - let alone redone, & have sat in my garage with my 914 on blocks for 24 years, after 13 as a DD for me & orig. owner before me.
The pix above give you an idea of how & where to repaint the background at the rim & spokes, as well as the center cap design (repro replacements are available from vendors at TheSamba.com classifieds).Hope this is helpful to all interested.
Good Luck Sean!