If you want to come just a little bit further south than Holden Beach to Ocean Isle Beach, quite a few home owners list their homes on a rent-by-owner website in addition to VSBO.....I am not sure if it's ok to or how to post a link so I'll DM you with the website and anyone else can DM me if interested.
It's how we found the OIB home we have rented for a highly discounted rate in the offseason as an alternative to trying to rent one of the few apartments in this area- we've rented a canal home for much less per month than what it rents for per WEEK in peak season.
So if you look through this site, you see photos and info about the homes and you contact a central person who will then put you directly in touch with the owners. It's a whole network of homeowners and rent is much cheaper than through realtors. The homeowner has the say in how much to charge, and then they send you a contract because this is a vacation rental under NC law. (Our longer term lease fell under landlord/tenant)..I am not affiliated with any of the owners in any way, don't know any of them, I've just used them myself this winter. For Ocean Isle Beach, it's coming closer to the peak months though so you may not be able to get a good discount much longer--however these owners are motivated to rent and if you want a last minute rental they'd probably rather rent and get some income rather than let the house sit empty, so last minute rentals would probably be highly possible....in peak season it's going to be much less likely that they have a lot of vacancies though, peak is basically Memorial Day thru Labor Day. I'm there right now and it's picking up but still pretty deserted. Just in case you are interested. If so you can DM me..I'd post the link if I was completely sure it's within TOS. It should be since I'm not affiliated with it or soliciting for it, and it's in answer to your question but I'll leave it that..
Just send me a message if you have any interest.