There are a few PBY kits to pick from. Minicrap makes a tiny 1/144 kit that is sold in a few versions. Its not a great model and is pretty small in 1/144. Airfix still sells their 50 year old 1/72 kit. It's a bit rough nowdays. Academy sells a few versions in 1/72 and those are pretty nice and probably the best PBY kits in that scale. From time to time Revell turns out their old 1/72 kit as well. It dates back to the 1960s. In 1/48 you have the nice Monogram kit (now Revell) which has also been sold in a couple of versions. This is a well done kit but very large. Czech Model showed a 1/32 kit on display at the IPMS nats in Orlando last month. Its not on the market yet but will be HUGE.