In general terms I think a vintage airgun has to be pretty bad (ie extensive rust pitting) to merit a reblue and the fact of the photo etching makes reblueing a bit more problematic where the Standard models are concerned. On the other hand... if the etching is long gone anyway, I suppose it doesn't make much difference.
I think my main objection to reblued vintage BSAs is that they end up so black and shiny, whereas the original BSA finish was a kind of steely grey-blue (or that's what it looks like 80 years on anyway!). Can this can be replicated? So far I've only ever seen reblues done with the kind of 'Venom-style' mirror polish deep black finish.
My last thought is that you obviously like what your mate has done to his, so that's what matters really. Who cares what anyone else thinks?! If you like what's been done to the Haenel (and I bet you will), get the Standard done too. And when someone finally gets their act together to offer affordable re-etching, you can put it back closer to the way it was when new!
PS I can't see any problem with picturing dead animals in posts, as long as they were shot legally.
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