If you cannot find a direct Nextep link, the NE510 often uses standard chipsets (like PL2303 or CH340). Identifying the chipset in your Device Manager can lead you to a generic driver that works perfectly.
Do use "driver updater" software. Instead, use these verified sources: nextep ne510 driver windows 7 link
Are you having trouble with the printer showing up in your , or is it failing specifically during the test page print? If you cannot find a direct Nextep link,