I wouldn't register the .com that is available to register, so I certainly wouldn't touch .bet, "swag" doesn't fit the niche in any way shape or form imo.
Swag.bet could be an affiliate site for betting promos and freebies, but even then it's a bit of a stretch and your limiting your end users to affiliates or a throwaway promo site, affiliates have have limited budgets for domain acquisitions and tend to prefer exact match domains.
Reg fee.