Maybe submit it to squadhelp unregistered, but pay attention if someone else submits it too, he will see the name was already submited and he might register it himself
Squadhelp is a domain marketplace; Welcome to NamePros btw
You can create an account here https://squadhelp.com
There are multiple brandable marketplaces, but most of them do not accept unregistered domains (squadhelp accept them, but it's a bit risky)
if you are a first time buyer, almost all registrars offer steep discounts to new customers. Google search for coupons for new users, you might get a great deal, maybe even as low as $1 per domain.
If you still need help, Epik.com can sometimes also purchase the domain and lease it to you with a purchase option. Depending on the domain we can likely help there. PM for details if still an issue.