Not a resident of Ghent but I love that place.
I believe there are some local online sellers that you can find easily (quick DuckDuckGoing should find you some), but be ready with a crypto wallet. Also heard that it works to ask students, especially if you are a student yourself, they would be lax about it and help you. Another good idea would be to go on a quick vacation to the Netherlands, get it from there and bring it back. Make sure to use a sealed smell proof bag. If I'm not wrong, you won't get into too much trouble since belgium has decriminalized possession and personal use as long as it's under 3 grams.