Hoses over 4 yrs old, good idea. Rovers North and Atlantic British are a couple of on-line sources. I'm sure more will come. Try Ebay too.
my gut says that they're just old. Previous 2 owners said they never changed them. Head gasket was changed 4 years ago, driven on the highway for 2 years, and then parked for 2 years. I just started driving it again.Consider getting a block test done and testing if your hoses are blowing because they are old or under too much pressure from a head gasket leak.