Yes of course, please take not there are comboboxes next to the field scd_start and scd_end.
Next to scd_start (or what ever your field name is) you can choose "Input field".
The component fulfills exactly your needs.
If you actually have all time slices in your source, you do not need the tOracleSCD component. I guess you have 2 task:
Initial loading of your data (with the already existing time ranges) --> use tOracleOutput
incremental loading with SCD because you detect the change date in your job or in your sources --> tOracleSCD
It does not make sense to get the scd_end date also from the source because everything what the tOracleSCD component supports is already done.
If you want to add surrogate keys, you can do so by using a sequence function which is part of Numeric functions. Here you could add the table max as the starting value. The table max could be stored in a variable before being used in the sequence function.