Oil Pressure gauge freaking out

Coronet 500 said
That doesn't look as bad as I was expecting.

It's just never done this so it's freaking me out. Usually is rock solid steady

I was just told that it could be my oil pump driveshaft gear popping up enough to cause the erraticness in the gauge and that I should buy the Hughes collar
http://www.hughesengines.com/Index/products.php?browse=search&search=collar&submit=Go&partid=25200