Harbor Freight sells both SAE and Metric 0 rings of good quality, in several boxes of assorted sizes, which I have found very helpful, including for putting smaller diameter batteries onto cameras, etc.
These kits are no expensive.
Get a 20% off coupon from weekly flyers in the weekly mailers, Popular Mechanics, or online, either printed or copied onto phones or pads; HF will take the electronic copies, no worries.
I will also mention that prints can be cut by very sharp razors, for resizing, etc and be rejoined with super glued such as the Loctite high strength Red 'thread lock'.
Many items at these stores have become very good quality, and are improving all the time, so if you think HF is just junk, you should think again and make a visit.
Their hand tools have lifetime replacement, like Sears Craftsman Line did for many years.
No, I do no work for HF.
Cheers.