there are probably as many names for this utensil as there are indian languages
here is a picture of a rather fancy one, but brass sev presses/idiappam makers/sevainaszhi/string hopper makers/chakli presses etc are for sale in most well stocked indian supermarkets. - usually brass
I saw one idiappam recipe that said that potato ricers work just fine for this too.
ps. I have a picture of a press on a tripod as in your picture in Chandra Padmanabhan's book Southern Spice. She calls it a sevainazhi or idiappamnazhi. Her description of how it is used is to make sevai, where the dough is steamed and then put through the press, a laborious task.
Here is an online description of this.
These presses are also used with raw dough for all kind of noodles and snacks, which would be steamed or deep fried. Most of the presses one sees in supermarkets are not on a stand
re: jen kalb
Yes I am sure that "sev" is called different things in different languages, but all of these utensils like puttu makers and so forth people use the English word "press" or "maker."
Incidentally I was in a multi-lingual group of women yesterday and I asked if there was any other term for sev press and they agreed on "vermicelli press." Lots of English words are used in all Indian languages.
If you note in the first picture link you attached, it says the word "farsaan maker." I thought of instructing the query person to go to a Gujarati grocer because they will surely have such a press as Gujaratis usually make their farsaans at home---but I have no idea if s/he would understand what I mean by Gujju grocer, so I left that part out. My Gujarati neighbors have a sev press that is a hand held version and has a twisty handle part on top. It has two changeable faces, one for fine sev, and one for fat sev. That model would be widely available at any Asian grocer that carries these types of cookwares.