Good catchall cashback cards known for giving high limits?

I only recently started building a credit history in the US (oldest account is 9 months) and am looking for a decent catch-all card with a relatively high limit (I want to be able to put a 6k/month AirBNB charge on it). Currently I have

Robinhood Gold - 1k limit

Chase Freedom Unlimited - 2.2k limit

Capital One Savor - 1k limit

AirBNB doesn't let me split a payment between multiple cards, so for now I'm just paying with a debit. Ideally I'd like to be able to take advantage of the 3% cashback on Gold but RH doesn't allow manual limit increase requests. I recently just got a limit increase on the Chase, and I can try asking Capital One for a limit increase but I doubt they'll let me jump to a 6k limit

I have good credit in Canada with sufficient limits, but I want to pay with USD. I've heard one option is getting a card from Amex Canada, then applying for an Amex US card using my Canadian credit history.

Are there simpler options, maybe a card that's known for giving higher limits but still has decent cashback? My credit score did improve quite a bit since I first got these 3 cards