You can order weck jars in the US, and I did so, because, resuale seals and cute jars.
They are OK for water bath canning and absolutely suck for pressure canning. Even using 4 clips as recommended when pressure canning, the seals extrude and then no seal is made. Secondly, once you break the seal, you only have a lid that sits on top the jar . So when your kid flings the fridge door open, the lid on the jelly jar goes flying across the kitchen . Unless you keep clips on it, which are kind of a pain.
Mason jars are way cheaper, seal more reliably under pressure, and are easy to obtain locally.
Incidentally, you can reuse the Mason jar lids by boiling them. Once it's hot, the red sealant will melt back into the edges of the lid. As long as you don't bend up the lid, you can get 3 or 4 uses out of it.