I removed the Tach from my 90 dakota, is not working see prior post. The back of the tac there is a silver canister that I need to buy. Pull of the dial and 2 screws and can right off. Any idea where I can buy just that part instead of the whole gauge?

 

I see you are in Hawaii, try to find an instrument/speedometer repair shop over there, they may be able to help you out. most times any of the individual parts for the gauges are not available to the public as the gauge needs to be calibrated.
For a used one you can try www.junkyarddog.com or www.car-part.com

There are a number of places online that repair tachs,gauges, and senders, etc. Here's a few...
www.gaugeguys.com
www.autoinstruments.com
www.redlinegaugeworks.com
www.dashusa.com
www.tachman.com
www.bobsspeedometer.com
www.williamsons.com
www.american-classic.com
www.speedometershop.com
www.ccspeedometer.com
www.dandmrestoration.home.mindspring.com
www.paspeedo.com
www.clocksandgauges.com