Usually the requirement for medical professional to take, seal, and sign the sample arises from said sample being needed for some legal purposes, necessitating an added layer of trust. In such case there may be extra paperwork worth more trouble than taking the sample itself.

Reading between the lines, this doesn't sound like such case. But in a remote chance it is, the legal context may create an obstacle for any doctor legally employed in China - foreign or not.

Might anyone know if above mentioned place(s) still exist, or know of any other brick and mortar store in Kunming for buying/browsing electronic components?

Specifically I'm asking because kid's electric toys have started to break down, and the little engineer is getting old enough to appreciate opening the broken toys and seeing/recycling what's inside. So would like to give him a visit to a shop that sells all that stuff.

Yes, spending the required time in HK, Macao or Taiwan would reset the clock, but of course this assumes status quo on these regions remains until 2024. Also not knowing the specifics of tax residency in said territories themselves.

But is it really 31 days? I seem to recall it was 3 months, which for me is a bit long for a single holiday trip even every 6 years. 1 month sounds too easy for most expats. But maybe I remember wrong or confuse with older regulation.

Yes, got it done now. Apparently the problem (at least today) was that the staff working at the entrance didn't know that foreigners can get tested there too. Today one of the ladies tried to call her superiors to confirm, but nobody answered and finally they just let me go.

Yesterday they were probably just not bothered to go through the hassle and said what they could - "No", "Yellow".

Anything is possible. Anyway I went again with wife after 17 yesterday, and checked again this morning after 8, and all the neighborhood testing stations were closed both times.