The 'Wellgood Loop' was conceived by Dr George Smart, M1GEO who had owned and used a Wellbrook Loop for some time, but which - to use his words 'in a moment of madness, he transmitted into it and blew it up'. It aroused his curiosity as to what was inside the Wellbrook, so got a chum to X-Ray it, and as you say, he discovered that the WB was built on stripboard.
He remarked that 'since this webpage went online, I have been contacted by many amateurs regarding failed loops. Primarily the cause seems to be either transmitting into the receive-only loop, or, water ingress'.
He designed and constructed his own version including a PCB, which he can supply.
He's written it all up, with X-Ray pictures, full constructional details of the 'Wellgood' loop and showing why water ingress has been a problem with failed WB loops. The link is here:
https://www.george-smart.co.uk/projects/wellgood_loop/
Hope that's of interest.