Question: I want to buy gifts for our non-Jewish clients. Can I buy them non-Kosher food and wine?
Answer: The Shulchan Aruch (YD 117:1) writes that one must not do business with any food which is forbidden to eat mideoraisa. The Rema writes that one must not, therefore, buy such food for one’s non-Jewish workers as one stands to benefit from giving such gifts (See Kaf Hachaim YD 117:28).
The Taz (YD 117:2), however, allows buying such food for workers, arguing that such gifts do not constitute business (See Shach YD 117:3).
The Shulchan Aruch (YD 87:1) writes that meat and milk that were cooked together are assur behanaah, forbidden to benefit from. Therefore, if one received such a food product, one may not even pass it on to a non-Jew. The Rema writes that this does not apply to foods that are assur miderabanan. Thus, one may buy food that is bishul akum, etc.
Nonetheless, the Kaf Hachaim (YD 117:52) writes that even those poskim who are stringent would allow buying gifts for non-Jews. Likewise, the Aruch Hashulchan (YD 117:19) writes that one does not need to spend more money in order to buy Kosher food.
The Aruch Hashulchan (YD 117:28) and Kaf Hachaim (YD 117:47) write that if one received non-Kosher meat, one may pass it on to a non-Jew.
The Rema (YD 123:1) writes that as there is a machlokes about the status of non-Kosher wine (stam yeinam), one should not benefit from it unless one will make a substantial financial loss. Therefore, if one receives such a bottle, they may rely on the lenient authorities and pass it on.
In conclusion, one may buy non-Kosher food to give to non-Jewish people, though one must not buy meat and milk cooked together or non-Kosher wine. One who receives such wine or meat may pass it on, though.