[HomeBrew] help needed

[Xu]

 Hi!
  I'm planing to home made a
 RF power amplifier.But in
 our country I can  not get Amidon's products(FT series), I can
 get the  torid core, some of them ,can work in 0.5-30MHz,
but"Mi"is too low,only have50-100,not as FT series of Amidon.
 my question is:
 How can I
 I use them in HF power amplifier as transformer and
  LBF inductor replace FT and T series?
 I think I can not use the brass tubes in the transformer
 of   HF power amplifier because of it
  has verylow Mi.
  Thanks in advance
          73! Xu