A while back I got a resin kit for a water tower from Anyscale Models. It's a nice small size just right for 009, and the stone base fits well with Hexworthy. It came with some wire for pipework, but no outlet for locos to use, so I found a corner of plastic sprue and carved out the resin to set it under the tank, the filler bag is a piece of electrical heat-shrink insulation and a wire handle was added for operating a valve.
The problem with the Peco buffer stop is it looks a bit flimsy, not so bad on the end of a long siding but it doesn't look very substantial if used on a platform or running line. For the bay platform I beefed up the Peco moulding with some diagonal pieces of plasticard, suggesting hefty timbers set into the ground to reinforce the stop beam. It's simple but does make the little buffer stop look like it could survive a gentle nudge.