The beads of rice bracelets themselves are the same as for 18mm watches - it's the endlinks that are different.
517 end links work on the jumbo Connies (I've tested 14777s and 168.001s). They are, however, very hard to find. This doesn't necessarily express to expensive - more often than not you'll find them on some other reference with 19mm lugs that is offered by a seller who is unaware of the scarcity of them. While a 18mm 1502/11 can be found for 200$ or so, I'd plan with easily 50% more than that. And since it's certainly not unrealistic to hunt for them for a year or so without finding one, I'd even consider going a bit over the top when, at last, you do come across a pair, as you'll never know how long you'll wait for another one. No idea if Omega produces a modern iteration, might be worth asking.
