There really aren't any. There's the pentium anniversary edition like the g3258 which is a dual core unlocked cpu. Then you have the i3 series which are dual core with hyper threading, 2 cores/4 threads and they're all locked cores. Next are the i5 series which is what you have and the 4460 is probably one of the least expensive 1150 i5's and has a locked core. The only 1150 i5's that are unlocked and can be overclocked are the 4670k and 4690k, the 4690k being the least expensive at the moment at around $219.
Is overclocking something you just want to do? Feel you need to do? Overclocking does make them faster but to get that feature costs more. Locked core i5's like your 4460 are still strong cpu's even without being overclocked. It depends which game you're trying to play at 60fps, every game is different. There are games out now that won't hit 60fps even with an i7 4790k (stronger than anything amd has to offer) and a gtx 980 gpu which runs $500+ just for the card alone.
If you simply want something cheap to overclock just to say you overclocked it, I'd grab a pentium g3258 for $65. Overclocking can be enjoyable, a sense of satisfaction at achieving a particular goal but usually for people who have an overclocked system they spend a day or so messing with settings, testing it for stability, fine tuning, retesting - and then leave it alone. It's not something you do once a day or once a week unless overclocking is your hobby or you're a competitive oc'er.
In that case, you're not using your pc to check email, facebook, gaming - you're simply spending your time pushing your hardware as fast as it will go and when that's done moving onto a new project. Many serious overclockers who do it constantly and compete have lots of hardware around and try several cpu/motherboard combinations to squeak every last bit of performance out of it. They also use things like liquid nitrogen to cool the cpu's, not air or water cooling like most people. It's an expensive hobby.
If overclocking is your main interest then yes, amd would be a cheaper way to go if you want something to oc that will perform better than g3258 dual core. Just keep in mind, you'd be giving up your current cpu, buying an amd cpu and downgrading your system performance to the point that you still don't have the performance of the i5 after overclocking the amd cpu. Whichever is more important, spending a day or so messing with it and being able to say you overclocked the amd you had to go out and buy or keeping what you have and having better overall system performance. It's your decision.