Well I dont know if OP is out of this bearing game or not but I am impatient so I sought out parts elsewhere. For anybody looking to improve the action on their Domino, I can tell you for sure upgrading bearings makes a huge difference... The bearings that came in the Domino and presumably the same ones in the Southard are possibly the worst bearings I have ever seen in a knife... But I love the Domino for a great many reasons so I wanted to give it the action it deserves... I started by ordering a set of stainless bearings from usaknifemaker, this is the set here..
https://usaknifemaker.com/caged-ball-bearing-set-ss-1-4-dia-set-2-bearings-2-race-washers.html Now the OD is more important then the ID on the bearings and these are a decent fit but they do leave a little play on the OD, its not bad and you will never know if you get this set... The OD is listed as .0416... However being the crazy dude I am I would be much happier with Ceramic Bearings (OCD) so after a great deal of searching I found a set, they are a tad smaller in the ID and OD then the stainless set I bought, But I ordered then anyway to see how they work out, worst case scenario Im out $10.. The Ceramic Set is found here..
https://www.bocabearings.com/products/f5-10brc-i0002085 Now the other big thing is the washers... Those awful tin foil washers Spyderco used, So what I did was ordered a set of PB washers from usaknifemaker... These were listed as .250 ID and they were a good bit to big OD to fit in the recesses of the Domino, but thats nothing a few minutes with a dremel and some sand paper wouldnt fix... These are just a hair thicker then the stock washers and a good bit sturdier, though they do not cause any problems at all after installed... usaknifemaker does have a smaller set of PB washers listed, but at the time of this post they are out of stock... With the new washers and stainless bearing set installed the action is infinitely smoother. I spent all of $8 at usaknifemaker for this upgrade... and it was only that much because they have a minimum number of PB washers you can order... How well the PB washers will hold up will be known in due time..
Meanwhile the biggest problem with the Domino is actually the Detent, so the next part of my action improvement project is going to involve drilling the detent hole a tad bigger so the detent ball can seat deeper and replacing the stainless detent ball with a ceramic detent ball... I expect this to make all the difference in the world... however I am currently not sure what size the detent ball actually is so i do not know what size bit I will need or what size Ball to order... I dont have a Micrometer so if anybody knows the size of the Ball please let me know, Thanks...