As the GTX 750 Ti is not terribly fast I would not think it horrible to pair it with an FX-6300. It is not an Intel chip like you want but it is not a weak chip either. It's quite affordable, most times you can find them for around $100. It is an AM3+ chip though, which is an aging socket. If you go to upgrade your graphics in the future to something really high-end, I fear there'll be a bottleneck. It has six physical cores but each core is not very strong on its own, so games that use only one core (the majority of games today) will not run as well as they would on an Intel chip.
The FX-6300 is still, however, a decently-powerful chip. It is very popular. I use one to power the server that my friends and I host games on.
If you don't mind a dual-core chip, then the Pentium G3258 would not be a bad choice either. It's not as powerful as the FX-6300 (only two threads, could be a problem), but it's a great overclocker and it's even cheaper than the FX-6300 (I think as low as $70 in some places). Using a G3258 also opens up a lot of upgrade options as it uses socket LGA1150, which is the most popular motherboard socket at the moment. In the future you could buy a stronger (much stronger than anything using AM3+) chip in the future, if you desired.
If the G3258's performance doesn't do it for you (it is after all not that great having only two threads), then any Haswell Core i3 (Core i3-4150, Core i3-4350) would not be a bad choice - they have two threads per physical core. Haswell's single-core performance is great, so even on a dual-core chip your gaming performance wouldn't suffer much. Only in multi core-using games like Battlefield 4 would you have a problem. Both chips in the parentheses also use LGA1150. They are however a bit more expensive than the G3258 and FX-6300.
And if you want to push your budget a little, the Core i5-4440 offers superior performance to all previously-mentioned chips (even the six-core FX-6300), and has four physical cores. It's about $170, so if you're looking for a budget chip you might be turned off by that.
Good luck.