New Member home-cheese in this post (https://cheeseforum.org/forum/index.php/topic,2405.0.html) asked: "I'm looking to buy a pasteurizer include chiller - 30/50 liter".
It's a good question and not many people look in the Geographic type boards so I'm reposting here to get (hopefully) a better response.
Check out MicroDairy Designs www.microdairydesigns.com (http://www.microdairydesigns.com). They might have what you're looking for. I found Frank Kipe to be very helpful.
I think Schiller (sp) had a few used ones. Search dairy suppliers or resellers.
Hoegger Goat Supply also carries them, along with cheesemaking supplies, too. http://hoeggergoatsupply.com/xcart/home.php?cat=49 (http://hoeggergoatsupply.com/xcart/home.php?cat=49)
We do make these. 50 l pateuriser, triple wall, agitator in the lid, curd knive. picture of a similar vat is here: http://picasaweb.google.com/blo4kka/CheeseMakingEquipment#5424089560907380450 (http://picasaweb.google.com/blo4kka/CheeseMakingEquipment#5424089560907380450)