H81 mobo and stock cooler would give you OC your G3258 to ~4.2 Ghz. For more you'd need an aftermarket cooler.
PCPartPicker part list:
http://pcpartpicker.com/p/yDsVLk
Price breakdown by merchant: http://pcpartpicker.com/p/yDsVLk/by_merchant/
CPU: Intel Pentium G3258 3.2GHz Dual-Core Processor ($69.99 @ Amazon)
Motherboard: Gigabyte GA-H81M-DS2V Micro ATX LGA1150 Motherboard ($54.68 @ OutletPC)
Memory: G.Skill Ripjaws Series 8GB (2 x 4GB) DDR3-1600 Memory ($72.00 @ Newegg)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($53.98 @ OutletPC)
Video Card: XFX Radeon R9 270X 2GB Double Dissipation Video Card ($159.99 @ Newegg)
Case: Antec One ATX Mid Tower Case ($35.99 @ NCIX US)
Power Supply: SeaSonic S12II 520W 80+ Bronze Certified ATX Power Supply ($65.98 @ SuperBiiz)
Total: $512.61
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-10-13 08:09 EDT-0400