What's it from ? The datasheet doesn't look super magical, but IDK mosfets that well. There's probably some cheap ebay ones that would do ok, and there's probably ebay ones that would do just fine. Then there's trying to search on the Digikey and other places, by spec's. If it's just some basic slow switch, probably anything with a small enough VGS threshold should do, and similar current and Rdson values.