I've seen them for sale on Etsy

Rareexotic seeds has Rhipsalis, but it does not tell the species; https://www.rarexoticseeds.com/en/rhipsalis-seeds-mix.html

I have bought seeds from them before. Nice looking seeds.

Bob Smoley has a good collection of Rhipsalis, and has clavata just for you.

I dont understand?

Rob Blomquist : Bob smoley's website lists pieces of unrooted Rhipsalis cuttings for $2.00 Not worth it at all. I'd rather spend a few more dollars and get a full plant

I have 8 dollars worth of cuttings and am a very happy man. Sorry it doesn't please you.

I checked out his site, $15 minimum plant order......... $18 shippping. I will be better off with a full plant at that rate.

Look on Etsy and Ebay. On Facebook there's also the Succulent Marketplace. You tell them what you're looking for, and you will get several offers of full plants. I have no time or patience for cuttings

https://www.ebay.com/itm/Rhipsalis-Clavata-Jungle-Cactus-epiphyllum-cacti-exotic-succulent-plant/333461507590?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160908105057%26meid%3D4ef4c42e6cc14601bfb650f86c428890%26pid%3D100675%26rk%3D3%26rkt%3D15%26sd%3D193266682710%26itm%3D333461507590%26pmt%3D0%26noa%3D1%26pg%3D2380057&_trksid=p2380057.c100675.m4236&_trkparms=pageci%3Aa38a3155-30e8-11ea-ba46-74dbd1801ebb%7Cparentrq%3A7d816f0016f0a12931171514ff917e2c%7Ciid%3A1