Need Zenith porthole flybacks

[Keith Park]

Hi all,
Doing 2 12" 23G24 portholes and both need flybacks, anyone have one?
one is an S16204 and the other S17244

THey should interchange with s-16566 thordarson # fly52 , merit
# hv0-53 , triad # d-45r stancor # h0217 and ram # x070 or Stancor Catalog lists a 'A-8268' as a replacement for the S17244

Any leads appreciated, got the rest of the chassis done and am itching to fire it up (without the fire this time) ;-)

Thanks

Keith