More experienced members here, what do you think of these coins I have linked, from this seller in Russia? Seems like they're cast and have weird painted on Toning/patina https://www.ebay.com/itm/Coin-Hawaiian-cent-1847-hapa-Haneri/392367251165?hash=item5b5ae91edd:g:dOYAAOSw2ipdRcKx https://www.ebay.com/itm/Coin-1-pesso-1881-year-Argentina/392374133721?hash=item5b5b5223d9:g-8AAOSwdzNdTHI5 https://www.ebay.com/itm/Coin-Thaler-1817/392280600152?hash=item5b55beee58:g:Yy4AAOSwiFhcuswE
I would definitely pass on all 3. They look fake to me, especially the Hawaiian One Cent coin! It's hard to say how or what country they're from but they don't look right at all.
I would not base coin authenticity on where the sellers are located. That's just poor numismatics. Who knows, the fakes could be made in Eastern Europe, China, South America etc - fakes / illegal stuff are out there as crooks know they can make money on it.
There are certainly plenty of fakes offered by sellers from places other than Russia. There may well be honest sellers in Russia offering legit US coins. I just haven't seen any yet on eBay.
There's another Russian seller that uses the exact same wording. Neither of them have a single legitimate coin for sale as far as I can see. And even if I thought they did, I still wouldn't buy it.