You are sending the transaction to coinbase, which makes you not able to use CPFP as you implyied. But let me ask you these two questions to know if you can still avoid using paid accelerator.

Do you use a wallet that support replace-by-fee? Like electrum wallet. If so, try to confirm if the wallet is replaceable, if replaceable, you can easily pump the fee?

If you have change address UTXO, you can still make use of CPFP. All you will need to do is to spend bitcoin from the change address and send it to another address on your wallet (or spend part of the UTXO in another transaction), but using a high fee like. The mempool recently dropped, 84 sat/vbyte will get single transaction confirmed now, so multiply it by 2 and minus it by you last fee will be the good fee you can use for now.

If you can not use CPFP, then just wait is the best advice.