The difference in model and OS can change (but not necessarily)
1) Your options for a forensic acquisition (and whether certain data can be decrypted)
2) Your options for a non-forensic acquisition (and whether certain data can be decrypted)
3) What jailbreak methods will work if that's needed
4) The file or file locations for certain data
Accurately and definitively identifying the model and OS are absolutely the first priority.
As stated, apologies.
I am aware of the implications of the change in model, but I mean for this case.
I already tried dumping a 4 with oxygen, version 7.0.3 but to no avail.
Most software will extract E mails from an iPhone 4. However your problem is the IOS7 software. There have been 3 releases of IOS7, I believe, and not all are supported by mobile phone software yet.