I found some peckoltia on an importeurs website. Drove there (for 2h) and found those peckoltia. I took 5 of them with me.
Importeur said he ordered wild L134. Definitely didn't get some. So he labeled them as L15, P. Vittata. But told me they would probably not be Vittatas

He hinted at maybe L477. But I can't find pictures of juvenile L477.
Looking at young P. Vittatas, I can find quite some similiarities. But knowing young peckoltia, they all look kinda like one another in their first months.
One of them has a coloured belly, the others don't. He also has a higher contrast than the others. Some L477 are said to have color pattern on belly whereas others don't. Maybe really L477? Sadly I didn't takle a picture of the colored belly

But at least one of them had a black yellow pattern on his belly and 3 others didn't, not sure about the last one.
they are 5-6cm TL. 4-5cm SL.