To answer your questions - initially they were from a brand that, well, has been bought out by another company. Which is a pain. None the less, I do have a link for you - and anyone else interested - and check out the selection for the gauges they have.
As for the installation of them... really, REALLY simple, and user friendly. Hope this helps.
http://www.glowshiftdirect.com/index...TS&Category=24