Is it permissible to sell products plated with silver, knowing that it is forbidden to eat and drink from silver vessels, and that the percentage of silver in these products is small; and do I bear a sin for selling them, and if so, what should I do?

The most cautious approach is to avoid using and selling items coated with silver. Therefore, it is preferable to seek another job to avoid doubts. If leaving the job immediately causes hardship, then it is permissible to continue temporarily until another job is found, due to necessity, and to try to dissuade the customer from buying such items if possible.