Digging around the box of boat spares, I've found a nice stainless steel prop setup to which I can fit a nice plastic prop. Placing it on the boat side, it looks like a good fit so I join the hull halves and deck together.
The kit is old and the part fit not perfect. I'm guessing that the hull has distorted a little over time joining the halves was a little bit of a fight. Plenty of liquid glue and much holding along with a couple of bulldog clips worked for most of the length, but the stern didn't want to play ball with a good millimetre of gap - if I could have got a clamp on it this wouldn't have been an issue, but there wasn't much chance of this.
Instead, I warmed up a soldering iron and melted the plastic over the join inside, letting it cool and do the holding for me. Amazingly, this seemed to work, allowing the glue to do it's job overnight.