Flyback xfmr substitiute. I need a sub for the flyback on a kv-25xbr about 20 years old. Part no.

Question

I need a sub for the flyback on a kv-25xbr about 20 years old. Part no. 1-439-339-12. I changed the horizontal oscillator transistor which was getting super hot; but still getting low voltage from the xfrm