I am trying to find sites that can create one(or two)-off
stickers/vinyls that are transparent. From what I am getting is that
it may not be profitable enough to make it worth the company's time
but if they did one-off batches (multiple client) would it not be
possible to be worthwhile?
Something that you have to understand when it comes to production related services there are factors companies (like digital printing) have to put in play to be profitable. I will use your issue as an example:
Say you have two stickers that come to be a total length of 12" in material. It costs you another 6" material to feed it through the printer and another 6" to feed it through lamination (if you are going to get it) which is considered as material waste because some machines require X amount of material to be able to be fed and printed on. The setup time is the same, you have to enter the design you provided, check to make sure its a correct vector, load the material, align the material, cut the material, etc. etc., and hit the print button. After printing, if they have a plotter, they will run it through the plotter and it will cutout what you needed..
Now you order 24" in material and my material waste is deleted and my production setup and print times dont change.. If you order 144" of material what are the factors that only change? Material, print time.. So that is why its better to order in bulk and small orders are usually not allowed or there is a min. order charge when placing orders because it will take the same amount of time to print 12" of stickers VS 24" of stickers (plus a little increased in print and plot times).. If you print 12" of stickers you are probably going to break even which means you will be out of business soon..
Am I going the wrong route? Is there a better alternative for putting
graphics on hobby projects?
I think maybe but since you haven't posted an example of why you need to go transparent I will just explain the differences. Transparent vinyl is a lot more expensive than simply white vinyl that can be printed on. I would ask why do you need it to be transparent. Do you need to actually see through it? If no, then look into die cut stickers and we do have a question on it: "What term is used to refer to cut vinyl stickers?".
PS: If you know where I can get one-offs you can post those in the
comments below my question
I think you may be looking in the wrong areas and I say that because searching online for one-offs you simply wont find it because they are looking for large, profitable, runs. Your best option would be to scout locally and use services like Craigslist, Facebook, local user groups, and you could even go to meetup and look for a local printers group where someone is doing this has a home hobby or starting out. I would also consider going into a local sign show and asking for a sheet to printed of your design and see if they will cut costs and you can just peel them off yourself like a very large sticker book.