RetroCase for RPi3B/3B+
Include: Case, Switches, Screws, Stickers, Accessaries, Assembly manual.
Check here for more assembly instructions
Price : $32.99
Compatible with PC, Raspberry Pi, builtin auto-fire function is easy to switch on/off.
Wonderful button feedback, stuck free, and zero input latency.
Cable length : 1.8m
Price : $11.99
Heat Sink Kit for RPi 3B/3B+
You don't need a fan when running Retropie on RPi 3B/3B+, heat sink is enough.
Material : Aluminum or copper
Price : $2.99
Included in Retrocase kit, this sticker kit can also apply on Famicom Classic.
Price : $1.49