RCA 630TS Need IF Coil - IF Osc. Issue

I'm new to vintage TV restoration and this is my first post to this forum.
I'm currently restoring an RCA 630TS television and have just completed
a full re-capping (minus the micas) and some resistor replacement. The
chassis powers up fine and all voltages are close to what is stated in
the service manual voltage chart.

I had to perform a complete video IF alignment because the 3rd IF coil
was destroyed by mice. I was able to replace the damaged coil with a
Merit TV-102 and I was able to achieve a decent swept video response
with one exception, I'm getting RF interference on channel 7 that seems
to be fed back through the tuner. The Merit coil did tune broadly during
alignment and I suspect possible IF parasitic oscillation.

Does anyone know what might be going on here? I would like to locate
a stock replacement 3rd IF coil, RCA p/n 71426. Suggestions on where
I might locate one is most appreciative. To rule out a possible source of
external RF interference, other televisions in my house do not exhibit
the Ch. 7 interference on the same coaxial line. Thanks for any and all
assistance with this most perplexing problem.

Mark G.