yes, minister (britbox at AP)
yes, prime minister (britbox at AP)
bottom (britbox at AP)
the new statesman (britbox at AP)
hillstreet blues (HULU)
st. elsewhere (HULU)
only fools and horses (1080p available, but pointless imo) (britbox at AP)
allo allo (britbox at AP)
good eats (first few seasons (DISCOVERY+ at AP)
next few are in HD, but look ok in 540p:
the nanny (HMAX - go for HEVC, protip)
the head of class (HMAX)
step by step (HMAX)
full house (HMAX)
whose line is it anyways (HMAX)
plebs (AP)
note: minister series are on AP last i checked and SD only, but two episodes out of cca 50 were available in 1080p over on AP (britbox channel iirc). also pointless since the source material hasnt been remastered, so it actually looks better at 720 or even 540p (went that route with 'allo allo', difference in sharpness was obvious, but at the same time it was way less blocky, which i prefer over the sharpness).
genereak rule of thumb: download first episode of season01 and see hows the quality. if not remastered, expect anything. if remastered, quality might surprise you (in a positive way). i usually go for s01e01 since most of the time all first seasons are filmed in a cheaper manner then lets say season05 (the office, modern family to name a few). as the series progresses and it becomes more popular, better lighting, cameras are used. which can mean a lot when it comes to these older, nonremastered, series.