The survival or otherwise of regional and national t.v. folk programmes may be debated at:

https://missingepisodes.proboards.com/

Also a search here might be fruitful ...

https://www.tvbrain.info

Then use the 'Search Lost Shows' search option.

Example ... here's a lost show that will never see the light of day again ...

https://www.tvbrain.info/tv-archive?showname=ballad+hunter&type=lostshow

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The existence of shows in the dusty archives however does not mean that they can be accessed, viewed, or copies obtained; and indeed their continued survival relies upon the expertiese and inclination of the donors &/or curators.

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