So I sent them an email, stating the issues. Two different people replied. Regarding the pickguards, the first guy says that they're not intended for their bodies, but as replacements for genuine Fender P-bass. I replied and said that perhaps the product page should say that. Another guy replied, saying that if I juggle it around (his words) it might fit. The first guy replies again and says a similar thing. I replied again and said that the photos I'd sent sorta prove that no amount of "juggling" would make it fit.
Regarding the ding, they were non-committal about how it might have happened. I did say that there was no damage to the shipping box, so it was probably like that when it left their shop. They initially offered 10% refund, upping it to 20% in a subsequent email even though I didn't ask for it. So on a 50 USD dollar body I got 10 back. About 13 AUD. Woo hoo. Better than a poke in the eye with a sharp stick. Just.
Oh well, let that be a lesson to me.
I saw a neck on ebay (Chinese of course) for 69 AUD. It appears in the photos that the rosewood fretboard is longer than the maple neck by about a quarter of an inch, so maybe if that fits it might just negate the ill-fitting pickguards. Only problem is, it's not finished. So would have to do that when it was my goal to *not* have to do that. Sigh.
The other thing I thought about was, instead of getting a custom pickguard made, use the one(s) I've got and convert it to a J-bass style. My J-bass has a metal "tail" (for want of a better term) where the knobs are. And a fair few other Fender models have a similar arrangment. The pickguard is in two parts, one plastic bit, one metal bit. So I thought of getting some brass plate, cutting the pickguard(s) and making a plate to fit over the route properly, and join them up. Only problems with that is 1) not much of a metal worker and 2) would have to get it chrome plated, which would probably cost a similar amount to getting a custom pickguard made.