I can’t find this exact set on the internet for comparison. The dollar and quarter are Philly and the half is Denver. From what I’ve found with some quick research the only proofs are from SF. These sure look proof. The coins are pristine - any flaws are on the plastic case. Any ideas?
Yep, just an aftermarket holder. As stated, looks like the Ike has been plated. The Half and Quarter look cleaned.
No. Plated is bad. Basically kills any numistic value the coins would have had. Luckily, the coins in question are common, circulated coins not worth more than face value.
You can separately get each of those coins in proof condition fairly inexpensively. The side by side comparison would be remarkable.
As mentioned, that is an aftermarket set put together outside of the mint, and the coins are either plated with something (chromed, perhaps), or just really harshly polished. I'm afraid they're not worth much more than face value as-is. You probably would no longer think they look like proofs if you held them next to a real proof set.