You're linking round o-rings, vs the square profile that come with the faucets. Probably not a huge difference either way.
But, you're also linking 3/4 inch OD rings which are definitely too big.
Buna-n:
http://www.amazon.com/dp/B000FMYONC/?tag=skimlinks_replacement-20
Silicone:
http://www.amazon.com/dp/B000FN0XE0/?tag=skimlinks_replacement-20
Yeah, it's hard for me to do this without having the faucet yet. It will be another week.
I did it based on 15mm x 2mm dimensions and not realizing that they are really flat washers and not o-rings. (Flat O-rings are washers!) The "Hong Kong" e-bay reference were actually sold as 15x2mm ones, but likely are round.
And... for the first time ever (because I measure them differently, I always do ID and thickness as the tables are that way...) I swapped ID and OD.. so you are correct that -016's are not the right size. 15mm OD-2mm Thick= 13mm ID thickness 2mm... If that is the case then the -014's (and I argue not -013's) are the correct size according to the tables I use, that Marco Rubber one being the easiest. That was the discrepancy.
So.. well.. the method has been 100% solid on O-rings from American manufacturers, anyway. Like a #204 silicone makes a dandy forward seal for both a Perlick 630 and a 525. Use them on both. Big improvement especially on the 525.
I wonder if the Intertap being all metric and, ugh, British Straight Thread, will make it harder for us to source O-rings as I can see some tolerance differences already... hmm.... Hong Kong eBay...
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Edited to say: I hope I can use a round silicone O-ring.. the square ones are pretty much nitrile only and are expensive little buggers.... Will try with a set I have at home when I get the faucet and will update.
Also, the linked Metric Buna-N rings in the original post are 13mm Od 11mm ID 2mm width. Did you actually mean
http://www.mcmaster.com/#1171N158? Those are 15mm OD 13mm ID x 2mm width. At $6.88/25 those likely are the best "square profile" or "washer O-ring" out there, even with shipping tacked on. I am actually somewhat amazed in how few places carry them compared to the normal round ones. This was a far longer internet search than I expected!