No need to fear being flamed for a legit question. That's a pretty big issue that you have potentially pointed out since you can only craft one crown, so you should only be able to buy one dingy. Seems like a loss of plat to me, perhaps this should be brought to the attention of STS and it should be looked at.

Can you even stash the dingy, because if you can I guess you could put a rush job on another 56 in order to craft another crown, however time is running short. If you don't make it I think that you should definetly email STS about this issue: support(at)spacetimestudios.com (replace the (at) with the @ symbol). How did you even get the option to buy two, can you buy another before completing the quests because when I try to talk to the fallen prince again I get a message and my only options is to say "Okay" so...