[Heathkit] HW-8 and HW-7 toroids?

[Tom NØJMY - AAR7FV]

Question for the QRP guys.  I have an acquaintance who is in the pre-wound
toroid business.  I have him contemplating offering the problematical
4-toroid HW-8 output set for 80 and 40 meters.  So far, every HW-8 I've
encountered needed new ones to get back up to rated output, due to
permeability changes.  Granted, I've only encountered three, hi hi.

My question is this: does the HW-7 also use the same parts?  I was thinking
I was told that the HW-9 did not, but that the HW-7 did.

Can someone clear me up on this one?

Tnx es vy 73,
Tom