I have just the one version of this which is in MP3 and which I downloaded back in 2012 maybe earlier. I'm not entirely clear when you say D2 in Part I doesn't match the listing on Discogs. The track D2 on your FLAC version corresponds to what I have. My version is entitled Bright Spark and is 1:42 long same as yours. Discogs has it listed as 1:38 long which I reckon is close enough bearing in mind this could be an estimate from the original vinyl by whoever entered the data on the site.
I've searched elsewhere on the web including the De Wolfe site as I suspect you have. But so far I haven't found any other versions of the track.
BTW thanks for the FLAC upgrade!!