With an OD of 1.45," I would go with a "dash number" of 127 (1.424" ID x .103" thick), 221 (1.421" ID x .139" thick), or 324 (1.35 ID" x 0.21" thick). That'll give some stretch to the o-ring so it won't fall off. Of course, that assumes you're going over the outer diameter. If you're looking to fill in the grooves, you'd probably want to go a size or two smaller depending on the measurement of the groove itself. I don't know how well-stocked Lowe's and Home Depot are for o-rings, I've never really paid attention, but Ace Hardware is usually good. Though the stock can vary from store to store. My personal favorite for ordering industrial-type supplies is
www.mcmaster.com. They have just about everything.