Imposible to known since 4.6GHz is kinda a high oc for such an "old" chip (old is the sense that if its a used part it may have been oc already and so it could have some degradation. Its not the same "that high" if we are talking about a brand new CPU, which is probably not the case here).
Besides that:
- Not every cpu overclock the same.
- If that i7 have a few years of services so is unknown how much voltage would it need to be stable at 4.6GHz, and thus how much heat will it need to disipate.
- OC results also depend on the motherboard, ram and psu.
If you want cheapper thats the only one I can think about. It should be enough for a decent OC.
How much will it give you in terms of frecuency?, imposible to know.