I was curious, so I just checked on one of our customers (I work at a small MSP in the UK) by way of comparison and we have on chugging along happily at more than double those numbers on a $288 Linode dedicated CPU instance. And we're only on that size for ease of disk space handling as the database is several hundred GB. CPU is basically at zero, it's the disk IO that actually gets you on some of these busier databases (from my experience).
RDS is extremely expensive. All managed databases are.
That said, it's a trade off of convenience and being in the AWS bubble, and weighing up the pros/cons of separating out services. Data Transfer is another thing to consider too of course. Sticking your database elsewhere might cost more in egress traffic communicating with it from your other AWS infrastructure. If you're all in on other AWS services, sometimes the RDS price is just worth it when it comes to the total price. Sound like this might be the case for your setup.
I hope you do manage to work things out. The service you have is great.
PS - Side note on RDS sizing. You might already know but sometimes it's worth increasing the storage size on gp3 type storage above 400GB (if you haven't already) as you get 12,000 IOPS baseline against 500MiB/s throughput[0] when you have that much storage. That's 4 times the below 400GB baseline performance but you only pay for the additional storage cost.
It can make a difference if you're IOPS constrained or trying to deal with bursty traffic but want to use the smallest instance size possible otherwise to save costs.
RDS is extremely expensive. All managed databases are.
That said, it's a trade off of convenience and being in the AWS bubble, and weighing up the pros/cons of separating out services. Data Transfer is another thing to consider too of course. Sticking your database elsewhere might cost more in egress traffic communicating with it from your other AWS infrastructure. If you're all in on other AWS services, sometimes the RDS price is just worth it when it comes to the total price. Sound like this might be the case for your setup.
I hope you do manage to work things out. The service you have is great.
PS - Side note on RDS sizing. You might already know but sometimes it's worth increasing the storage size on gp3 type storage above 400GB (if you haven't already) as you get 12,000 IOPS baseline against 500MiB/s throughput[0] when you have that much storage. That's 4 times the below 400GB baseline performance but you only pay for the additional storage cost. It can make a difference if you're IOPS constrained or trying to deal with bursty traffic but want to use the smallest instance size possible otherwise to save costs.
[0]https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_...