Are you talking small transformers, or the ones that take months to replace?
The generator step-up transformers are rated at 220mva each 18kv/138kv.
Not more than a football field away is a hub. Their xfmrs are 1000mva.
They do have a couple of “used” spares on site and grounded out. Wouldn’t matter though, if the protection relays and breakers are inop transformers are not gonna help much.
These take a year or more to build. Less if it’s just a rewind.
Then it falls back on who can get their generators back online, but if the transmission is down....
The RTO has a “plan” to bring the grid up, but that’s assuming all the parts are still working.