Danny, I think for the long haul you might want to consider self hosting your own image gallery. You can get a managed hosted bundle Chevereto gallery from as little as $46.20 a year which includes hosting and the gallery software licence. I know it would be a monumental task to edit all your thread image links but paying PB $400 a year is a non-starter.

I setup a test site last night using their free version and it seems to work pretty well, even with castrated free version functionality: https://www.airrifle.org.za/