Can I Use Items Purchased With Income Earned From a Doubtful Sale?

No, the income you earned earlier will still be considered halal, provided that the item being sold was itself halal and the act of selling was fundamentally permissible according to Islamic principles. In your case, since the fragrance itself is a halal item, the earnings from its sale are considered halal in principle.

However, since you later came to know that this practice was against the company’s (eBay’s) policy, then continuing this activity knowingly would not be permissible, because it involves violating a contract, which is a sin. Therefore, stopping this practice and repenting is necessary—and you have already done that, which is the correct approach.

The Islamic principle is that as long as an activity is not inherently haram, the income derived from it is considered halal. If a person later finds out that it was against a company’s policy, the previous earnings do not become haram, although continuing it afterward would not be permissible.

Based on this:

The shipping bags that were purchased from that income can be used in your new halal business; there is no issue in doing so.

It is not necessary for you to buy new supplies; using the existing ones is completely permissible.

However, for further peace of mind, you may give a small amount in charity if you wish.