2nd hand i7 and reassess situation.
I would be tempted by this, second hand 2600K or 2700K (Or maybe even an Ivy Bridge i7 if cheap enough) will do fine.
...And then start considering a CPU upgrade again when AMD Zen/Intel Skylake/Cannonlake is out

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2nd hand i7 and reassess situation.
I would be tempted by this, second hand 2600K or 2700K (Or maybe even an Ivy Bridge i7 if cheap enough) will do fine.
...And then start considering a CPU upgrade again when AMD Zen/Intel Skylake/Cannonlake is out.
2500k is easy mode overclocking, even a noob like me can manage it.
Mine will do 4.8 on a low profile (ish) cooler, with a decent AIO or monster air cooler 5ghz shouldn't be an issue IMO.