I don't know this particular set, but Umberto di Fiore is a renowned maker and has been working for many years.
The price is very good indeed. If I had the money (and need for a third zampogna), I'd buy them right away.
The bag seems to be made from an inner tube, because the seller mentions a little valve to remove condensed water when necessary. If you are interested in this instrument you should consider getting a natural goatskin bag for it.