Oil Tank Gauge?

[bigdog]

Hi Folks....

I have a 275 gal. oil tank which has a defective 'gauge' on top of tank which measures amount of oil in tank.

Looks easy enough to replace by myself, but want a professional person who is familiar with these systems.

Besides, using a oil dealer maintenance technician, who could replace this
gauge? Oil burner tech ? Licensed Plumber?

And can you buy these gauges in a hardware or plumbing supply company?
Have priced on Internet avearging about $25.

It's a long story, but don't want to go to current oil dealer for service,
for this gauge replacement, unless I have to... Location Gilford-Laconia area.

All suggestions appreciated !

Bigdog