All: more vise companies than Parker made wrenches for their swivel bolts. since it doesn't have any markings or the Parker's jaws i'd say not a Parker. i''m not an expert on the smaller open screw vises so i'll post to kick it back up to the top and maybe somebody that owns one of these might post what your vise is. do you like it and are you planning on keeping it?
also looks like it's your first post so do you have other vises and please post your vise family. also welcome to our group.