Anyone import Forecast Overrides? Is it a thing?

As in SFA forecasts?

yes. we currently do not use estimates or opportunities but would like to use the Override fields on the Forecast Form to hold static "budget" numbers by Sales Rep

Nah you can't import em unfortunately. Only option would be to import to a custom record and then use a script to copy the value over... IF (and that's a big if) the forecast record is even exposed to scripting. My gut tells me it's not.