Thanks for the responses.
To clarify the situation a little more, we will be receiving an export from a 3rd party company and will have no access to the source system. We are simply building a system from this, to be able to retain certain audit data.
It will indeed be a Homogeneous copy.
"Could you share your SAP Basis component release and SP level?" - already did - "The source system is ECC6 EHP4 SP5 (Oracle 11.2.0, Linux)" - I don't have any other details at this stage I'm afraid.
We don't have a Solution Manager system. We don't have any other SAP systems. This will be a one off system build.
Are we able to use SWPM without SolMan?
I've looked a bit more into SWPM and I appreciate the point about not requiring specific version Installation media - as this effectively replaces it (I believe we would need 70SWPM); indeed, I can see that there no longer is any Installation CDs in the download centre! So we just need to DB & kernel software (possibly Java, not sure yet if this is a dual stack system or not).
I would then ask which kernel media should I use, the one from ERP 6 or the one from NW 7.0 - but there isn't any under ERP 6!
So, hopefully I should have enough to work with for now, just need to read the SWPM guide fully. Thanks for the steer in the right direction!