Interesting unit. The logic board and power supply have obviously been replaced. But the case lack vents common to later units. The serial number tag might've been pulled and reapplied. Keyboard appears to be consistent with a unit of that vintage.
The shot of RF modulator appears to have vent hole above it but other photos do not. In the same photo the velcro stub on the lower case appear to be flush but other photos shows it as not. This listing looked suspicious.
The Monitor IIe is interesting too; it has an amber tube inside a unit clearly marked as being green phosphorous.